Plugins create feedback loop when session opens in 7.4 cs3

[a guy]

I recently upgraded to PT LE 7.4cs3 and concurrently upgraded Reaktor to 5.1.5. I'm running OS X 10.4.11 (Tiger) on a Dual 2 GHz PowerPC G5 with 4GB of RAM. My interface is an mBox and I've been running PT and Reaktor and other plugins on this machine w/out problems for about 3 years now.

I originally thought my problem was limited to using Reaktor 5 in PT, but on closer examination, any plugin I try to use causes the same problem. Here it is in a nutshell - I created several sessions of music last year (prior to upgrading) and I first noticed the problem when I launched an old session. Audio channels were using instances of Reaktor 5 as a plugin (guitar distortion) and also the bombFactory compressor. That's about it for plugs on those sessions. When opening the session I get a nasty feedback loop (sounds like a delay unit on inifinite repeat - or maybe a 1/4 second piece of audio played on 'loop'). Every channel with a plugin and the master all show meter signal from the sound. This is while the transport is at rest. When I start playing the tune, the feedback gets replaced with the audio (at least on some channels) - I've had varying success with that. As soon as I stop the transport, the feedback returns.

Thus far I've tried writing both Digi and NI asking for help - neither were able to recreate the problem. I sent a session file but never heard back. I've tried changing number of processors used, % of computing, cache, just about everything I could find in troubleshooting advice that seemed like it might help.

Nothing has worked thus far. I'm about to upgrade to cs5 but seriously doubt the issue will be solved.

So, I'm hoping someone that reads this has run in to this problem before. Are my plugin prefs corrupt? How do I fix that? Is there just some sort of broad incompatibility that I'm overlooking based on my system? As I said i originally thought it was limited to Reaktor until I opened a sessions using the BF compressors and had the same feedback.

Any help is greatly appreciated. I'm now sitting on several songs that I'm unable to mix or work on further w/a system that's essentially disabled.

Frustrated,
A.Guy

[Phil Ogden]

For the limited effort involved, it's certainly worth trashing prefs and databases. Detailed instructions are contained in the general troubleshooting thread at the top of this forum.

If that doesn't work, try removing third party plug-ins and putting them back one at a time. As above delete prefs, empty trash and reboot/relaunch Pro Tools. This process should help eliminate a problem plug-in.

After that, a clean reinstall of Pro Tools might be the way to go.

http://www.myspace.com/philogg

[Slim Shady]

I'd probably target the Mbox as the culprit actually - your USB cable may be dying or the USB connection on the back of the MBox itself might be getting loose. If there's any way you could test your rig with a different LE interface (got any friends with PTLE?) as a test, that'd be a place to start.

[a guy]

I ran the PT troubleshooting utility (command line) and trashed the prefs. While existing sessions still have the problem, I discovered that after running the utility I was able to delete the instances of Reaktor on each track, then create an AUX input channel, bus the audio to it and playback w/out the feedback. It seems the bombfactory works just fine when Reaktor isn't feeding back, so perhaps it's only Reaktor causing this problem as I originally suspected. Thanks for your reply.

[a guy]

I just found out a friend nearby is running LE, so I'll see what his interface is and if I can borrow it for a day. Will also try replacing the cable as a start. Thanks for the insight!