Volume/Sound issues with synth apps when Auria open

[SSquared]

I've been suddenly having several volume/sound issues when running Auria with a synth app. I have tried Alchemy, Sunrizer and Magellan and so far, each one has a problem. The only thing that has changed is I upgraded to the latest Auria 1.091 earlier in the week. Probably doesn't matter, but I had skipped the 1.090 release and went directly to 1.091.

If no one is seeing these problems, I will reinstall Auria and see if that resolves the problems. Before doing this, I will backup the Documents directory. Is that basically all I need to backup or is there another directory with personal files? I just want to be sure once I reinstall, I can get back to all of my projects.

Here are very reproducible cases for me. In all cases, Audiobus is off. Background Audio is off. I have also rebooted the iPad. Removed all apps from memory. Auria is at 44.1. All the normal stuff.

For each app, follow these first similar steps:
1) Open the app.
2) Play a few notes to be sure things sound good.
3) Open Auria.
4) App Switch back to the synth

Alchemy
5) The in app volume slider no longer works.
6) Although using the iPad's volume controller seems to work.
7) Does not matter the order apps are started. If Auria is open, the Alchemy volume slider does not appear to work.

Sunrizer
5) Play some notes and everything is silent.
6) Opening up Auria THEN Sunrizer seems to work.
7) Turning on Auria Background Audio also seemed to return the volume to Sunrizer.

Magellan
5) It crashes. Sometimes it crashes immediately. Other times it waits until I play a note.
6) If I open Auria first and THEN switch to Magellan, the sound in Magellan is completely distorted and pure noise.
7) Using Audiobus does not appear to have this issue and works.

Sometimes I want Auria open, but don't want it in background mode, nor do I want Audiobus on. I don't recall having such consistent issues prior to just a few days ago.

[Rim]

What you're observing is unfortunately a consequence of some bugs in CoreAudio. What version of iOS are you running?

Auria uses a new category they introduced in iOS 6 called multiRoute. This allows Auria to send different audio to separate outputs. As soon as we started using this new mode, we noticed some issues with other apps running at the same time as Auria. It seems there are some bugs Apple needs to iron out. I've let them know about the issues.

Until they fix this, to avoid these problems, don't run Auria at the same time as these apps.


Yes, all your projects and other data are stored in the documents folder, so if you back that up, you've got everything.

Rim

[SSquared]

Thanks for the detailed reply. That was very helpful. I'm running iOS 6.1.3. I really appreciate the reply.

Most of these issues are rather minor, except for Magellan, but that appears to work when I have Audiobus running.

[Rim]

The magellan issue is a separate problem. This most likely happens because Auria uses a very large buffer size (4096 samples) by default. Some synth apps don't like buffers this large. Auria uses this large size because it uses much less CPU. If you start Audiobus first, Audiobus forces Auria to use a small buffer size (256 or 512). Of course, this also causes the CPU usage to go up, but at least it's usable with other synth apps.

Another solution is to put Auria into "Audiobus mode" in Auria's settings. This causes Auria to use a 512 sample buffer size. Again, this will cause CPU usage to go up.

Rim

[SSquared]

Ah, VERY interesting. Thanks again. That worked.