I originally posted about this dilemma in the Ableton forums, but it turns out it would be more relevant here, so i thought i'd repost it in case anyone has the same issue.
Post subject: Fuzzy midi notes with Alesis Trigger I/O
Posted: Tue Oct 09, 2012 3:47 am
My new Alesis Trigger I/O
arrived today and it works well, EXCEPT strangely after playing for around ten minutes all the midi coming into Ableton slowly grows more and more fuzzy--the midi from the Trigger I/O as well as from my keyboard, which has never had problems before. It happens slowly, over the course of say, 10 or 20 seconds, until the sounds coming out are completely distorted and unrecognizable. The Alesis is sending signals through USB and the keyboard is sending through a midi cable run through my Saffire Pro 40
interface. It happens whether the midi's playing a drum kit or a VST plugin. I would assume that the Alesis is just faulty, except that it causes the keyboard to go bad as well. I'll probably wind up returning the unit, but has anyone heard of this kind of problem? It's really strange that midi of all things should become distorted. I'm running Windows 7 on a new computer with plenty of processing power and I've never noticed anything unusual with Ableton's CPU Load Meter.
Post subject: Re: Fuzzy midi notes with Alesis Trigger I/O
Posted: Tue Oct 09, 2012 5:17 am
After more messing around, I'm not thinking it has to do with the Trigger I/O; it seems to be an output problem. If I record the distortion as it gets progressively worse, then stop and play the beginning of the recording where the audio should be fine, it will be distorted. This made me suspect my Saffire Pro 40
interface, which functions as my computer's sound card. I turned it off mid-session and started it back up and the sound was pristine again. So successive midi notes cause the Saffire to tweak out after a while? I'm not convinced. Once the audio has gone bad, I can also fix it by closing Ableton and restarting it, keeping the Saffire running. Also, it's only the midi that's affected. If I record normal audio simultaneously and play it back, the normal audio sounds fine, as does any other audio the computer plays. What is it about midi from a drum module that could cause this abnormality? I can play my keyboard through midi for hours and it doesn't cause this to happen. Also, once I restart either Ableton or the Saffire I can listen to the whole recording I made without anything happening, so just listening to a midi track doesn't cause it. Anyone have any insights?
Post subject: Re: Fuzzy midi notes with Alesis Trigger I/OPosted: Tue Oct 09, 2012 7:17 am
Next I tried setting the computer's playback to it's original speakers, disabling the Saffire. By doing so, I was able to play midi drums all I wanted without problems. So I set up the Trigger I/O to run through midi into the Saffire instead of through direct USB, and the problem was solved. The Saffire must not like to share bandwidth with other external devices or something (even though it's firewire, not USB). I still don't really get it, but at least it's solved, and I should still be able to run my keyboard and drums at the same time if I run the midi through the keyboard and set the instruments to different channels.