If there were only CC's in the beginning of a track then that's ok. But...on a good midi file and by that I mean one that was professionally produced, the author spent a considerable amount of time mixing the whole file so it would have good dynamics. Sure, you may want to delete all of that anyway and start over but I've found it's best to leave those alone.

What you should do then is render those tracks to audio. Now all of your controls including the mixer will work but at least you have preserved what the original author of that file did.

Bob

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