Glitchy Distortion to monitors but...

[GtrNamp]

I think I might have found a bug related to the latest version of iOS. I'm running an iPad Air 1 and I just recently updated to the latest iOS. Normally how I use MultiTrack DAW is in Audiobus. I recently, after updating, recorded a small song and everything was fine. I went to record again but this time all I got was a lot of glitchy distortion and strange sounds. Not like notes but very bass heavy random sounds that would change pitch as I played notes but they weren't the pitches I was playing. At first I thought this was an issue with an effect app I was using because when I removed it the problem stopped. But then after closing everything and restarting I got the distortion even without an effect. The strange thing is I tried to record the sound and it recorded the sound of my instrument as it should. I thought maybe this was a Audiobus issue so I deleted and reinstalled. That seemed to fix it for a while but today the issue is back. Is it possible that it's a monitoring issue with MTD?
I noticed another issue using InterApp Audio. I tried to add an effect to a track but I got a message that said something to the effect of I was loading an incompatible app. It was AUFX:Space. After trying different ways to get it to load I then got a message saying there were too many instances of the app already open. I attempted to open the app in the effects slot of Audiobus and noticed that the IAA control panel was up. When I tapped it, it opened up a menu that had about 25 or 30 AUFX:Space icons all partially transparent since none of them could be used. I removed all of them and this allowed me to use it again. I'm completely confused by all this.
Any enlightenment you can offer would be greatly appreciated. MTD is my favorite recording app. Thanks for keeping it going and thanks for any help you can offer

[pwnified]

Welcome GtrNamp,

I thought maybe this was a Audiobus issue so I deleted and reinstalled. That seemed to fix it for a while but today the issue is back. Is it possible that it's a monitoring issue with MTD?

Too weird. The monitoring path does take more cpu, but it shouldn't be that much. Are you using 'Input Monitoring' in the menu, because with it off, monitoring is performed by audiobus. It also could be an issue where the cpu throttles down the audio thread when it shouldn't. I've heard of some problems with iOS 9 doing this but I thought they fixed it.

I attempted to open the app in the effects slot of Audiobus and noticed that the IAA control panel was up. When I tapped it, it opened up a menu that had about 25 or 30 AUFX:Space icons all partially transparent since none of them could be used. I removed all of them and this allowed me to use it again

That sounds very strange. It's usually a bit dangerous to be using IAA and Audiobus at the same time, because of the limit on instances of the app (only 1 instance is allowed system wide). An app might not be releasing the single shared instance of the IAA plugin app. What IAA control panel are you talking about? And how did you remove them? If you could give me a step by step that would help to reproduce this.

[GtrNamp]

Sorry for my delayed response. I was having a problem with your support email but it was my issue. I accidentally inverted the n and i in the word harmonic.
Before I go into how I discovered the multiple instances of AUFX:Space I discovered something else that might be very relevant. I attempted to open an app in MTD using IAA. I'd open a track, select the in button then select an app. Any app I selected had the same effect. I would get the white loading box and it would disappear immediately. I would then select the arm button and then it would say " loading audio units" then the name of the app, say, Jordantron, and the arm button would go gray. It appears that for some reason it's trying to open audio units even though they aren't audio units. Maybe a bug with the latest iOS?
How I discovered the multiple instances of an effect. I was using Audiobus with MTD in the output slot and Line 6 MobilePOD as the input. I then loaded AUFX:Space into the effects slot. When it opened I could see a small panel behind the Audiobus transport bar. I dropped the bar and it was the IAA control panel. It showed MTD. I tapped the MTD icon and it opened to reveal a panel with the multiple instances of AUFX:Space along side MTD. All these apps were completely shut down before I loaded them in Audiobus and I even restarted the device so I'm not sure how this is even possible. The apps weren't just closed. I double tapped the home button and slid every app that was open upwards to shut them down. I then restarted.
As for input monitoring, I've always used auto input but I did notice that input monitoring did not have a checkmark next to it. I'll turn that on and see if it fixes the audio issue.

[GtrNamp]

Something I forgot to mention before, I believe the reason that there were so many ghost instances of AUFX:Space open was because it wouldn't work in the affects slot of Audiobus. Every time I tried to load it in the effects lot I would get no sound. So, I decided to use it in MTD through the IAA effects in the track I was recording. I simply tapped the FX button and opened the IAA tab. I'd tap the + box and select AUFX:Space. Instead of opening I would get an 'invalid format' message. I'd try this multiple times and it would never work. In fact, right now it's still won't work even when I don't have Audiobus running.
I'm going to post three pictures. The first is after the first failure in opening the app in IAA. Then I tapped the second IAA + box just to see what would happen. I got this message box. The last picture is showing multiple instances of an app that is not audio unit compatible. I hope these will help you.

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[pwnified]

I wonder if it's just a samplerate issue, is the project set to 44 kHz? Currently multitrack requires projects to be at 44 kHz when using IAA. That might explain the plug getting allocated but not initialized, hence the zombie instances. The next version will allow any samplerate by using converters.

[GtrNamp]

You nailed it! As I'm sure you have often seen, it is once again user error. I had been experimenting with different sample rates to see what would happen. I don't know much about digital audio recording so I am not entirely sure what this does. While experimenting I had set it at 96 kHz but forgot to change it back. Now that it's back to 44 kHz everything appears to be fine with the audio.
I'm having another issue though. When attempting to run input apps through IAA some have a hard time loading (I-SEM) and others won't load at all (Alchemy, Jordantron) while still others load right away without an issue (Patterning, Z3TA+). Is this a problem related to IAA?
Just one last question, when is it possible to run bit depth at 24? Is that for devices newer than the iPad Air 1 or is it dependent on the apps being used?
Thanks for your help! I recently had a friend buy your app because I felt it would be better than others. He'd get discouraged trying to use Auria, Multitrack Studio or anything else. Multitrack is just fun to use. Thanks!

[Telefunky]

same here with the M3000HD and several other apps that just don't load via IAA
I usually switch to audiobus then... never minded the details

24bit doesn't sound any different, in particular it does not sound more detailed or 'transparent'
on the other hand one usually ends with 24bit anyway because there's only a single setting for the project in MTD
highly dynamic sources like vocals or acoustic drums/instruments almost require 24bit

biggest advantage is more headroom, but decay tails in silent parts also benefit
while it's still good practice to properly set levels, 24bit is more tolerant than 16bit (stating the obvious)

cheers, Tom