Bug: Frozen Crash When Changing HW Device

[ashmatthews]

Here's how the bug/crash occurs - this has happened multiple times, the same way every time.

I open an existing session. Once everything comes up. I go to Setup -> Playback Engine...

Then I choose the new playback engine I would like to use, then hit Yes, then Okay.

From there, ProTools completely freezes up. Nothing happens no matter how long I wait. If I try to restart the Mac, it sits waiting for ProTools to finish.

[cwsand]

Originally Posted by ashmatthews

Here's how the bug/crash occurs - this has happened multiple times, the same way every time.

I open an existing session. Once everything comes up. I go to Setup -> Playback Engine...

Then I choose the new playback engine I would like to use, then hit Yes, then Okay.

From there, ProTools completely freezes up. Nothing happens no matter how long I wait. If I try to restart the Mac, it sits waiting for ProTools to finish.

No idea without any info on your system. What interfaces are you switching between?

Help Us Help You

[Eric Lambert]

I find that if I select the largest buffer size prior to making that switch, I'm less likely to get a crash. With small buffer sizes I get the beachball immediately after switching and it never returns. Whether or not this should happen, it does, and it has for quite a while across many versions of PT and Mac OSs.

[Darryl Ramm]

Hi welcome to DUC

Changing from what exact interface to what interface? At what sample rate and buffer size? (does the new interface support that rate?) Are any other apps or the system using the interface you are trying to switch to, Macs are generally good about multi-client audio devices, but try with nothing else using the device.

Is the info in your profile up to date?

If you hold down the 'N' key while Pro Tools is starting (keep it held down until you see the playback engine dialog) and pick the playback engine you want to switch to does it then hang? or work OK?

Is the driver for that interface up to date and claimed compatible with the macOS version?

What happens when you do this with no session open? With a new empty session open?

You should always be be starting by following some basic troubleshooting, see under "Help us help you" up the top of each DUC web page. Always starting with trashing prefs (use Pete Gate's PT Prefs utility http://petegates.com/pg-pt-prefs.html). And trash prefs frequently as you try other stuff. The other standard thing to try here that stands out to me would be to create a new admin account and test from that, and testing with a new empty session as well.

[ashmatthews]

Sorry guys, I thought the system info I entered in my profile would translate into posts.

2019 16-inch MacBook Pro
macOS Big Sur (Version 11.6.5)
2.6GHz 6-core Intel Core i7
16GB 2667 MHz DDR4
AMD Radeon Pro 5300M 4GB
ProTools 2022.5


The latest 2 crashes happened...

1. Changing from "Macbook Pro Microphone" to "UMC 1820"

2. Changing from "Macbook Pro Microphone" to "External Headphones"


I believe both times the HW Buffer Size was 128 samples. (I believe someone mentioned changing the buffer size first helped a similar issue"


In both cases, a hard restart of my machine then opening the same session, and changing the playback engine again worked fine.

[Darryl Ramm]

Originally Posted by ashmatthews

1. Changing from "Macbook Pro Microphone" to "UMC 1820"

2. Changing from "Macbook Pro Microphone" to "External Headphones"

One problem might be is you can't (or can but should not?) have a playback engine that is just the microphone. Pro Tools require a playback engine that has output channels.

Pro Tools has historically done an *awful* job dealing with this, often leading to a cryptic ASSERT crash. Maybe stuff has changed recently, but you should to make sure never to select a microphone as the playback engine, and if you need to use it then you need to create an aggregate audio device with say microphone and headphones. You can use the 'N' key to make sure the microphone is never selected as the Playback Engine, and maybe trashing prefs will help it being automatically selected.

Don't know if this may be related to what you are seeing, but either way you want to avoid that Microphone playback engine.

[ashmatthews]

Yea, I know that. I would never choose it purposefully. That’s just what PT defaults to when I don’t have an external interface plugged in for some reason.

[albee1952]

Best solution: change the playback engine with no session open.
Next best solution: set the buffer to 1024 before making the change

[ashmatthews]

Originally Posted by albee1952

Best solution: change the playback engine with no session open.
Next best solution: set the buffer to 1024 before making the change

I'm gonna try these out over the next several days, and see if either of them ever results in the freeze or not. I'll report back after some testing!

[Darryl Ramm]

Originally Posted by ashmatthews

Yea, I know that. I would never choose it purposefully. That’s just what PT defaults to when I don’t have an external interface plugged in for some reason.

If you hit yourself in the face with a hammer and it hurts maybe stop doing that.

Which is why I suggested the things for for you to do.

If you trash prefs Pro Tools will forget the last playback engine it used and hopefully pick another one. And if you pick the correct one and then exit Pro Tools and then start up again later it will remember your choice. If you don't have that interface powered on it will pick something else, if it's making a bad choice in those cases you start up Pro Tools with 'N' like everybody else has to. If you switch interfaces/don't have stuff powered on a lot just get used to doing that. Still try trashing prefs and see if its automatic choice changes.

This is all broken on so many levels. Starting with Pro Tools should easily be able to work out a CoreAudio (or ASIO) interface has no inputs and never select it, throw up the playback engine dialog if needed. It's like Avid developers working in this area just don't even care.