I knew you were going to ask this, it's fairly complicated. If you're using a VSTi (the i stands for instrument) to simply play back a recorded midi part, no problem. My Jamstix for example will play back any midi drum part perfectly using whatever drum kit I want. What we're referring to here is a VSTi that also is capable of creating it's own parts. Jamstix, BFD, Virtual Guitarist and also effects VST's like rhythmic delay's and others can create parts but those parts have to be linked to the tempo of the song just like the Real Tracks are. It's that tempo linking or matching with the host that does not work in RB/PT. The problem has never been explained fully but best guess is it's a problem with the VST implementation. If you don't have one of those plugin's, you would never notice it but considering the big name ones are not cheap (Virtual Guitarist is $399) it's a bit of a kick in the head to find out about this after you've bought one expecting to use it with RB or PT.
Hmm, I see I still may not be clear here. You're asking if you will have timing issues with a part and the answer is no. If you're using a VSTi as a playback module for any midi part either from a midi file or a Biab part no problem the instrument will follow any tempo changes happening. It's only one of these "special" VSTi's that can create their own parts that have the problem if your trying to use them in that mode. For example Jamstix has a separate "brain" page that's all about using it as a drum machine with tons of control over different rhythms. That function does not work in RB but on another page in the JS menu is the playback only functions. Those are fine.

Bob

Last edited by jazzmammal; 05/12/10 08:11 AM.
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