Starting play on playback plugin mutes other instruments

There seems to be a bug in playback plugin: If you are playing some software instrument and while it's producing sound you hit play on playback plugin, the sound from the other instrument stops. What I mean with "sound stops" is that the currently playing notes are cut out. After the playback has started I can continue playing normally.

This is disturbing, because in many tracks I perform I want to first play an intro, and at the end of intro hit play (using a footswitch) to get the backing track running, but a smooth transition from intro to backing track is impossible when starting the backing track cuts out the sound tail from the intro. It sounds very bad.

This does not reproduce always, but usually when playback is started for the first time after loading a patch. Sometimes it helps if I start the playback once and stop it: then the next time I hit play the other audio might not get muted. But it does not always help.

Using mainstage 3.0.1, and this was problem in mainstage 2 too.

However, I have a workaround: I create some silence to the beginning of backing track and add a marker spanning only silence. Then I start playback cycling the first marker. I play my intro, and when I want the backing track to start rocking I toggle playback cycling off using another foot pedal. However here's also a bug: if the silence marker cycle is too short (and I want it to be short to minimize the delay from toggling cycling off and rocking to start) the playback plugin fails to cycle the marker, it just goes through it and loops the next marker.