Distortion on playback

What are you using to record and listen to playback with?  Also how are you recording into GTP4, using a mic or a direct line?  Knowing your system a little bit might help a little as well, especially your audio interface. 

I can tell you that I've had more than 8 audio tracks going at once and I haven't had issue so it can be done, we'll need more info though to get to the source of your problem. 

Without knowing much else I have 2 things you might be able to go on.  First make sure you patched GTP4 to the latest and greatest.  Maybe there was a known issue that got patched. 

Next thing to check is the levels of all your tracks, make sure you aren't going into the red on any of them as well as your final output meters.  If you are excessively going into the red that is probably your problem.  Start quiet then slowly increase the volume. 

Another thing to check is if freezing the tracks helps.  Perhaps your system is having a hard time keeping up in real time and that could be why when you mix down everything for another program it sounds fine but playing it at real time is not working as intended.  By freezing the track it applies the effects and leaves the cpu and memory for other things.

Give those a shot if they don't work come back with some more info

Good Luck
Matt

Me again.
I just reopened the project I had the problem with, froze all the tracks and it worked! Brilliant! It enabled me to mix it the way I wanted. Thanks so much for your help.
 
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