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11.1.5 "Playback Record Stall" window on all recording

Posted: Tue Oct 23, 2018 04:34
by Mark Lemaire
Hello! It's been a while since I have posted, and I'm hoping this is an issue you folks have encountered before.

I have just installed PMX 11.1.5 in a brand new MacBook Pro/ Bootcamp. Since my last PMX upgrade was version five something, I have a learning curve to negotiate. I will try not to post with too many obvious questions.

So here is one I could 'defeat', but would like your advice first:

When I record, a “playback record stall” window opens and floods me with error messages-- telling me every second that

“Your recording may be at risk: write drive performance insufficient”

Hitting the space bar will not stop the recording. The only way for me to stop recording is to hover the mouse over the timeline and click, dislocating the cursor. However, if this window is already open when I start a recording, recording will stop in the usual manner – with me hitting the space bar.

I am only recording 16 tracks- 15 of them blank, one test microphone on track 8 with me counting to ten. The recording seems to come out OK.

Have others had this problem before? I could just disable this window, but I would like your thoughts before I do something like that. Thanks in advance for your help!

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Tue Oct 23, 2018 15:20
by fl
Hi Mark,

It sounds as though your machine is not as completely configured for Pyramix as you could hope...

I certainly hope that you're using an external drive for your media, and not the internal C:/ partition. You should read over everything written about configuring your hardware and the settings in whatever version of Windows you are using (always good information to include in a post asking for help) found in the Merging Knowledge Base: ... tion+Guide - particularly the section on configuring the Media Drive(s).

There are some basic configurations to perform: format the disk as NTFS with a block size of 64 kb, and make sure that indexing is disabled (in Windows Explorer, right click on your Media Drive, and select "Properties", and in the window which opens UN-check the box beside where it says, "Allow files on this drive to have contents indexed in addition to file properties"). Also, in the Device Manager, access the Removal Policy for your Media Drives and choose the option for "Better Performance" as opposed to "Quick Removal", which is unfortunately the default.

When recording, it's often helpful to have your machine off the internet, and then having all anti-virus/anti-malware real-time protection disabled.

What kind of performance are you seeing when you run a DPC Latency scanner like DPC Latency Check ( or LatencyMon ( You may have some other processes running which can interfere with the efficient transmission of audio data to and from an external media drive. One thing I know for sure, you should disable the Apple's Battery Monitor in the Device Manager, as this can introduce large DPC spikes every ten seconds or so. As long as you're running your machine from AC power, you should be fine.

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Tue Oct 23, 2018 18:03
by Mark Lemaire
Thanks, Frank, for all that specific information.

And I thought we had left the olden days where you have to write to an external drive!

Survey question: Do all forum members here using PMX native and a Macbook Pro record to external drive? If necessary, I'll go get one- and be sure it connects directly to one of the MBP's 4 Thunderbolt ports, rather than running through a hub.

On a side note- do other useres here know of a reliable, solid, and portable (no power wall-wart) hub that I can hook to the Macbook Pro to create some USB ports? I just purchased two Syntech Hornet Power hubs and, despite the great reviews, not all USB outlets function on both.

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Wed Oct 24, 2018 00:34
by Thomas Grubb
Hi Mark,

I’d be curious to know how you go running LatencyMon on the new machine. I recently bought a 2015 15’ MBP (being a recommended machine I thought my troubles were over!), but I haven’t been able to get it running reliably, despite doing all the optimisations as far as I can see - there’s an ISR/DCP spike every 10 minutes or so which can sometimes cause a click. I’ll make a change to the system and it works after a re-boot, but the next day the problem returns. Hopefully one day the drivers will be updated, but for now I’m using my 2012 Lenovo backup machine and the MBP is used, well, as a Mac!

For a recording drive I had been using a thunderbolt LaCie RAID drive, but noticed if I wiggle the connector it disconnects which doesn’t inspire confidence! For now i’m using an external USB3 SSD and backing up after a session.

A ‘frustrated and over computers’ Tom

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Wed Oct 24, 2018 01:43
by Mark Lemaire
Thomas- Thanks for you letter. So many folks have been using a MBP that I am hoping that trouble-free recording and mixing will be mine soon. I hope it works out for me- arrggghh!

As far as LatencyMon and other software Frank has mentioned, I have not used any of that yet. My busy day has kept me from the "new computer project". Before I do as Frank has suggested, though, I plan to look this page over in detail: ... figuration

Windows was installed on this MBP without knowledge of this info. Now, it seems I have my work cut out for me optimizing the Mac so it accords with this doc. So until that happens, I cannot speak to Frank's suggestions. And I'm going to be away for the weekend soon! I hope to break the ice on this page tomorrow.

As far as a hub/ external drive, MBP for 2018 have no I/O except for 4 thunderbolt ports. On this machine they have a strong magnet that 'sucks' the plug home. I doubt I could wiggle one loose, but there is much for me to learn yet!

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Wed Oct 24, 2018 17:17
by fl
Thomas -

I have a strong suspicion that it's your battery monitor that is responsible for your "every 10 minutes" issue. I'm running Windows 7 on all my machines (insert comment here about "cold, dead fingers"), but I believe that the method is similar if not the same in Windows 10. So try the following as an experiment:

1. Click the Start button, and then type "Device Manager", and select it from the list which appears.

2. Once that window opens, you should see "Batteries" in the list of folders - click on the plus box to expand its contents. You should see something named "Microsoft AHCI Compliant Control Method".

3. Right click on it and in the pop-up, select "Disable". You'll get a confirmation warning - click "Yes".
(Don't worry, you won't damage anything, or make a setting you cannot undo later - to reverse this change, simply follow the steps above, but this time, you'll be offered an option to "Enable".)

After you've done this, run LatencyMon once again to see if this addressed the "once every ten minutes" interruption.

You may be concerned that you could damage your battery, but in eleven years of running Windows on my 2007 MacBook Pro, this has never been a problem. I've never had to do a location recording without having AC power available, and I couldn't power my external drive, audio interface, mic pre-amps, etc. without it anyway. I do make sure that the battery is at full charge before packing it up for transport to my recording location, just so no automatic process could start up which could cause interruptions, or to generate heat. I leave this device driver disabled all the time, but if you prefer, you could disable it only when you know you're going to be recording, and then enable it once you're done.

If heat is a concern, as it is with almost every model of MacBook Pro, consider disabling other unnecessary Device Drivers in the Device Manager. Being clever in this way can result with as much as a 20 degree drop in operating temperature, which is significant when you're running close to the automatic shut-down temperature of 100 degrees C. I also use a USB laptop cooler, and I have installed and configured Crystal Idea's MacsFanControl to kick the fan speeds up at a lower temperature than what Apple has set -

Other likely candidates for Device Manager disabling include:

Human Interface Devices > Apple IR Receiver
(for the little hand-held media player controller that comes with most Macs. Call me old-fashioned, but I'm usually not watching a movie or listening to iTunes while I'm recording...)

Imaging Devices > iSight
(I'm one of those people who covers their computer's built-in camera with a post-it note anyhow.)

Network Adapters > Wireless Network Adapter, Bluetooth Device (Personal Area Network), and Bluetooth Device (RFCOMM Protocol TDI)
(This leaves the Ethernet connection, which I don't use on location recordings anyway, so I suppose I could also disable that as well. On the other hand, if you're using an Ethernet connected audio interface, like a Horus or Hapi, you'd need to leave this activated.)

Sound, Video & Game Controllers > Realtek High Definition Audio
(if not Realtek, whichever brand of hardware Apple installed in your machine. While you're at it, disable all Windows sounds in the Control Panels > Personalization > Sounds > Sounds > No Sounds. The last thing I want is some random computer generated bink or bonk to leak out to my microphones, polluting an otherwise clean recording.)

I hope this message helps with finding your way through the convoluted process of optimizing your system to allow efficient audio recording operations. There are a few more steps to take, but most of those are covered in the Pyramix Knowledge Base, as well as other places on the internet which can be found by searching for "Optimizing Windows 7 (or 10) for Audio".

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Thu Oct 25, 2018 01:01
by Thomas Grubb
Hi Frank,

Thanks so much for your reply - unfortunately i’ve tried all of those things. The Battery Method, and also the AC Adapter devices cause spikes, but the first one usually occurs around 7 minutes with those ones!

As it’s a new install, it’s Win 10 1803 which i’ve read has caused problems with other laptops in terms of latency spikes. I’m going to try and create a dual-boot Win7 system, or wait for a suitable Win10 update. For the moment my Lenovo T430s is working and TPFanControl is keeping the fan in check. Much easier to read screen on the MBP though!


Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Thu Oct 25, 2018 14:35
by fl
Sorry to hear that didn't work. I guess the only thing left is to go through all the drivers in the Device Manager window, disabling them one by one, then running LatencyMon for seven minutes to see if that was the one. Repeat until comatose.

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Thu Oct 25, 2018 23:29
by Thomas Grubb
It’s a pity I don’t do knitting because I already could have replaced my whole sock collection! I’ll let you know when I finally find the culprit!

Re: 11.1.5 "Playback Record Stall" window on all recording

Posted: Fri Oct 26, 2018 19:34
by fl
A few words about LatencyMon...

First and foremost, LatencyMon is a program which can help you IDENTIFY processes and/or drivers which cause interruptions which can disrupt real-time audio operations - it does not FIX them. However, once identified, even if the result is some cryptically named software file, you can do a web search to find more information, and with any luck a method of disabling the function or perhaps a suitable replacement.

If you're running Windows 10, you should use the latest version from the Resplendence website -

If you're running Windows 7, as I am, then use version 4.02 which was produced a few years ago when Win7 was the latest offering from MS. You can find this through Click on the "Version" button to select LatencyMon 4.02.

For best results, disconnect your computer from the internet, and disable any real-time monitoring performed by your anti-virus/anti-malware program(s). I use Microsoft Security Essentials on my systems, which can cause Hard Pagefaults every minute or so unless I disable the "Real-time Protection" found in MSE's Settings Tab. Users of Malwarebytes Premium should just quit the program. Other anti-virus programs, such as Avast have proven to interfere with Pyramix audio processes, so you may find you need to re-consider your choice of anti-malware. I'm not saying that you should disable all anti-malware whenever you run Pyramix, but that the issues that these programs create can mask other issues LatencyMon will see. So, for the duration of your test, turn 'em all off, however you can.

When you've done all of this, start LatencyMon and click on the Tools menu entry, then clicking on Options. In its "General" tab, uncheck the box next to "Measure SMIs and CPU stalls" - for the first test. "Apply" and close the Options window.

Start the test on the "Main" tab. Let it run for 10 minutes or more, making sure not to touch your mouse or keyboard for the bulk of the test, as these can skew your results. Just watch the meters on this page, and make a note of when any sudden jumps to higher values occur. Having some idea of the timing of these interruptions can help when trying to identify their sources. When you have what feels like enough data, Stop the test.

The main things you should be looking for are DPC interruptions, as they're the most likely to be intrusive, but are also among the easiest things to deal with. ISRs are less critical, which is why a useful test can be run without including their scan. A real-time audio operation can withstand large Hard Pagefaults without glitching (just so long as they're not too frequent), as there is usually sufficient RAM available to act as a buffer, so don't be dismayed if you see the meter for these going off into the red towards the right side of the Main tab. For example, my system runs a disk fragmentation check as a Windows Service every fifteen minutes, causing LatencyMon's meter to fill up all the way to the right, yet I seldom if ever have found this to be a problem while running Pyramix.

On the "Stats" tab, you will see entries showing information about the various types of interruptions found, including the source of each type's (DPC, ISR, Hard Pagefault) highest count. On an optimized system, this will usually be file names ending with the ".sys" suffix, showing that they are part of Windows. Remember that all these kinds of interruptions are part and parcel of normal computer operation. A computer which does not generate DPC, ISR and Pagefault interruptions is one that is turned off, so you have to use judgement when determining which of these are excessive and which are simply necessary parts of normal operation.

Further down the "Stats" tab, where you can see information for each of the kinds of interruptions found, with the source of the most numerous given in the second line of each section. On a well-tuned system, these will probably be file names ending with the ".sys" suffix, indicating that they are part of Windows. If you see something else, it may point to some third-party software you've installed, which is performing background polling or scanning of your system, or attempting to communicate with the software vendor or worst of all, with a virus or malware maker.

If you see a program you've installed and know about already, quit or disable it and run the test again. If you see a significant improvement, then you know that you either have to find a replacement, or learn to live without it. In my case, I've found that the use of Microsoft Security Essentials with its Real-time Protection enabled, is a source of large Hard Pagefaults, so I know that if I have a particularly heavy Pyramix project involving higher track counts, high sample-rates and word-lengths with a lot of plug-in processing, then I should take my machine off the internet and disable MSE's protection, then re-enabling it later when I'm done and want to re-establish contact with the internet. For what it's worth, I've found that MSE is one of the lighter and least intrusive of all the anti-virus programs out there. People have reported issues with Avast in the past, and I know it's not recommended by Merging.

Unfortunately, what you're more likely to discover is that some process or hardware driver is causing your grief. You can discover more information by looking at LatencyMon's "Processes" and "Drivers" tabs, where you can order the lists of items by clicking on the various column headers. Look for sources of Pagefaults in the "Processes" tab, DPC and ISR interruptions in the "Drivers" tab. In the Drivers tab, you can scroll over to the far right side and see columns for "Product" and "Path". Looking down the "Product" column, you'll see most of the entries are from Microsoft and are part of Windows, but if you see any which have high interruption counts that come from other vendors, then you have a serious clue as to the source of your pain.

In most cases, you'll find that a source of interruptions is stemming from some obscurely named piece of software or a driver with a ".dll" suffix. In this case, your best bet is to do a web search on the file name in question, and with any luck you will find information from Microsoft, which may not be all that enlightening, or better yet, forum posts from people who have already encountered the issue you're experiencing and, with any luck, instructions for how to mitigate it or them. Sorry, I can't be more specific than that.

If you've found culprits and disabled them, and now get much more favourable results from LatencyMon, go to the Options once again to enable the "Measure SMI and CPU stalls" item, and then run the test again.

If LatencyMon identifies a hardware driver as the source of your issue, you need to turn it off in the Windows Device Manager. To open this, click on the Start button and type "Device Manager" and then select it from the list which appears. I've gone so far as to place a shortcut to the Device Manager on my Desktop to speed this process. Once the DM is open, you can scan down the list of the various driver categories, opening up the contents of each until you find the likely suspect identified by LatencyMon. Right-click on it, and in the pop-up, choose "Disable". All the entries will disappear for a moment and then re-appear. If you look closely at the icon for the driver you just disabled, you should see a little square with a downward pointing arrow indicating that it is indeed disabled. If you close and re-open the Device Manager, you'll find that if there are any disabled drivers present, their category heading is already opened, so this is a good way to see what you have disabled, while providing the opportunity for you to enable them once again (right-click, "Enable").

The first time you do this, is probably going to be nerve wracking - "Am I damaging my computer?" "What if I can't find my way back here to undo what I've just done?" Keep notes as you proceed, detailing each step in the disabling process, so that you can re-trace your steps if you find you have to. After a few visits to the Device Manager, you should find that it's far less daunting that it was initially, and that you can use it as just another tool for running your computer.

People running Windows on Apple computers via Bootcamp should be on the lookout for Drivers which perform regular polling or scanning operations, such as the state of Battery charge, but also the ambient light sensor, the built-in camera, Bluetooth connections, as well as wireless connections of any type. If one of these appears to be the source of your issues, click on the Start button and type "Device Manager" then click on that when it appears in the list. You'll have to hunt for the driver you've identified, by opening the various categories displayed in the DM window. Once you've found the one you want, right-click on it and in the pop-up which appears, select "Disable".

Some recent MacBook Pro machines come with two separate graphics engines, one that is suitable for day to day operations, the other which kicks in when more intense graphics processing is required. Usually it's the change-over from one to the other which will cause huge DPC interruptions, so you'll need to find some way to keep your machine running in just one all the time. Some audio processing plug-ins can have heavy graphics requirements, in which case you should take care not to have their windows displayed when you are playing or mixing audio in case it taxes your graphics hardware at an inappropriate time like when you're Mixing or Publishing a big project..

If you find a likely candidate in LatencyMon, be it a piece of software you've installed, a driver which is hogging too much processor time, or - heaven forbid - a piece of malware gobbling up your system, you'll now be better equipped to find out what and where they are, hopefully allowing you to take the steps needed to fix things. With any luck, you'll be able to fine tune your system so that the only Pyramix projects you have difficulty with are those which demand more CPU, RAM, internal Bus speed, and Drive Access than your current hardware can provide, in which case it may be time to consider the purchase of a newer, more capable computer. However, with proper and appropriate optimization, you should be able to run most Pyramix Native projects with track counts of fewer than fifty tracks on just about any computer from the last decade, unless it's something which is crippled by design such as a MS Surface or other Tablet type computer.