fixed, just had to mix down to stems then import into a blank session, haven't had trouble before apart from crashing when using Melodyne. was mainly just checking it wasn't a common thing and I was doing something really stupid :P :D Is it best to disable the master track FX when doing this and app...

So basically in playback, everything is fine, but the moment I mixdown it has a continuous beep sound that gets higher pitched from about midway to the end of the track. it keeps rising. is this a problem or am I hitting a plunging error? it's strange because I don't hear anything in playback at all...