# Catastrophically Degraded Output



## king-1871 (Nov 20, 2021)

Yikes! Logic just developed another new problem that has ground all my music projects to halt. I sure hope one of you fine folks can help me remedy this.

Today when I opened a project and played it, the sound was extremely degraded. It sounds like the song is being played on a tiny transistor radio speaker with an extreme amount of distortion. It also sounds extremely quiet — maybe 15 dB quieter than it should. It’s just a tiny thin frazzled sound. The song sounded fine last time I worked on it, which was yesterday. Suspecting this particular Logic file might have gotten corrupted somehow, I opened a different, older project, and… same result: The song, which previously sounded fine, now sounds like its being played back on a tiny, tinny, distorted radio speaker, extremely quietly.

When I play back audio through iTunes or stream it through YouTube, it sounds fine, so I don’t think the problem is with my general audio setup (which I have not changed lately).

I should mention that I’m working on very old gear: A 2012 quad-core Mac Mini (with 16 GB of RAM) running Logic Pro 9 on Mac OS 10.12.6 (Sierra). It has worked fine until now. Logic has had its bugs, but nothing catastrophic like this. 

I’m beginning to wonder if this very old program is just becoming unstable, but I’m reluctant to upgrade to Logic Pro X because I’m in the middle of an album project, and have ten songs that were started in Logic 9, and are works in progress. I imagine that converting Logic files from version 9 to version 10 will cause more problems than it will solve, so I’d rather finish these in 9 before I make the transition… that is, if I can get Logic 9 to work again.

Two questions:


1 — Does anyone have a suggestion of how I can fix the degraded output problem?

2 — Does anyone have experience migrating a Logic project from 9 to X, and if so, what was the transition like? painless? Troublesome? A nightmare?


As always, thanks in advance for your input.


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## Ivan M. (Nov 20, 2021)

Cables? I remember this kind of problem when not inserting a TRS jack properly.
Is the sound bad outside Logic, in the browser, music player?


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## jcrosby (Nov 20, 2021)

Ivan M. said:


> Cables? I remember this kind of problem when not inserting a TRS jack properly.
> Is the sound bad outside Logic, in the browser, music player?


Hmmm, does it sound super 'digital' - i.e. almost like aliasing?

And did you recently update macos by any chance?

I had some really weird core audio issues that started after a macos security update a couple months after I got my 2018 MBP. I evenetually wound up having to restore from a backup to resolve the issue... Now I'm hella' careful about installing any macos update without a backup... Do some digging and you'll see that Apple has a really bad track record with core audio related bugs in the past few years.


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## king-1871 (Nov 20, 2021)

Regarding Cables: The sound is fine when playing audio outside of Logic, so I don't think that's the issue. Regarding a Mac OS update: I have not updated my OS in years. I'm still running 10.12.6 (Sierra), and have not installed any patches, updates, etc.


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## joed (Nov 20, 2021)

With regard to your question two, i had no problems opening any Logic 9 session in Logic X. I think the only issues i ran into were having to re-download some of Logic's Sampler libraries. Also, i'm using the same mac mini as you.


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## jbuhler (Nov 20, 2021)

Are you sure Logic is routing to your monitors and not to the computer audio or one of the other devices Logic sees as an output? I’ve had issues with Logic connecting to the wrong device in this manner.


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## king-1871 (Nov 20, 2021)

That’s a good question. I route my sound out of the Mac mini’s headphone /audio out jack straight into a pair of PreSonus speakers, and that’s where the tiny distorted sound is coming out, so I don’t think the routing has changed. When I look in System Preferences —>Sound, it indicates that the output is the headphone out jack. Am I missing something? It does seem to be an audio output issue. I just tried another experiment where I created a brand new empty Logic project, loaded one sound library, and played live on my keyboard — and the sound was the same — highly distorted and extremely quiet.


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## jbuhler (Nov 20, 2021)

Just checking: Have you restarted the machine? I don't see anywhere that you said you restarted.


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## ryans (Nov 20, 2021)

The sound you're describing sounds like it could be comb filtering?


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## king-1871 (Nov 20, 2021)

I just ran another test and discovered something interesting: I bounced a song out of one of these “corrupted” Logic projects, and the bounce did not have the quiet, distorted sound. It sounded fine, in terms of audio quality. But the bounce had a different problem: Some of the tracks were missing. In fact, most of them were. In between long silences, an instrument would pop in here and there at their appropriate cues in the song, but most of the tracks were not playing back in the bounce. Nothing is muted, nor is anything on solo. At first I thought that the tracks that are silent are the ones that are frozen, but then I discovered two or three frozen tracks that DO play back, so at this point, I don’t see a consistent pattern. Strange!


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## king-1871 (Nov 20, 2021)

jbuhler said:


> Just checking: Have you restarted the machine? I don't see anywhere that you said you restarted.



Good question -- and yes, I tried both a restart, and a shut down. Unfortunately, the problem persisted after both.


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## jbuhler (Nov 20, 2021)

How about GarageBand or another DAW? Any problem with those programs? Uninstalling and reinstalling Logic might be another option to try. I can't remember how much of a pain that was with Logic 9.

Also do you have a bootable backup from before you started experiencing the issue?


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## king-1871 (Nov 20, 2021)

ryans said:


> The sound you're describing sounds like it could be comb filtering?


To be honest, I have not heard comb filtering enough to know if that’s what I’m hearing in this case. The degradation is pretty drastic, and the volume attenuation makes is hard to hear the song at all. Whatever it is, it’s not a subtle effect.


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## jcrosby (Nov 21, 2021)

Programs don't just become unstable by being old, and Logic relies on the OS for all of its audio resources. Audio Units, core audio, midi IO, etc are all system processes not Logic processes. So it'd be smart to rule out any background updates that may have occurred (*especially if you have automatic updates enabled*) so you can start looking for other causes...

One thing you might want to try to rule out it being related to macos is quit Logic, launch Activity Monitor, and force quit the *coreaudiod* process. This just force-restarts audio across the system immediately. Then you would relaunch Logic and see if the behavior persists.

Also, have you trashed Logic's preferences? (This should be your last resort as you'll have to manually re-set some of your Logic settings).

FYI the transition from Logic 9-10 was painless for me, but that was years ago so there's always the possibility for things to be bumpy. However Logic X won't overwrite Logic 9 so you'd still have 9 available, and all you would need to do is save new versions of each project after opening them in X so your Logic 9 versions aren't impacted.

That said Logic X does change the location of some things. And Logic has changed so much from LPX 10.0 that it might actually be smarter to stick with 9 to finish your project first if you manage to figure out the issue and get it working properly.


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## king-1871 (Nov 21, 2021)

jcrosby said:


> Programs don't just become unstable by being old, and Logic relies on the OS for all of its audio resources. Audio Units, core audio, midi IO, etc are all system processes not Logic processes. So it'd be smart to rule out any background updates that may have occurred (*especially if you have automatic updates enabled*) so you can start looking for other causes...
> 
> One thing you might want to try to rule out it being related to macos is quit Logic, launch Activity Monitor, and force quit the *coreaudiod* process. This just force-restarts audio across the system immediately. Then you would relaunch Logic and see if the behavior persists.
> 
> ...



FIXED!!


JCrosby, your suggestion put me on the path to solving the issue. I tried using Activity Monitor to force-quit the Core Audio process, and although that did not fix the problem, it did prompt me to start thinking about the Core Audio aspect of Logic. I then opened the Preferences —> Audio panel and, under the Core Audio tab, I discovered that the Output Device had somehow gotten switched from “Built-In Output” to “HDMI”! I don’t know how that happened. Switching it back to Built-In Output restored the sound to normal.

Thanks to everyone for your suggestions, and especially to JCrosby for explaining how some of these audio processes work under the hood, and pointing me toward the Core Audio for troubleshooting.


I swear, I know just enough about this stuff to get me into trouble. I’m glad I have you forum folks to help get me out of it!


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## jcrosby (Nov 21, 2021)

Congrats on getting it sorted! Glad it wasn't related to an update. I had an issue on my 2018 MBP that I was able to trace back to a security update and the only way I could resolve it was to wipe the internal and clone from a backup... Glad it wasn't relate to something like that because that's no fun!


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