MTU.Community - "beep"

hello all,
i am trying out the hoster demo. i have a question up for grabs. when i make a playlist ,with singers,i will put some songs at different keys. when i play them i hear an audible beep, the song stops, then continues, then beeps again, stops, for the duration. the songs at level key are fine? someone know what's happening? please tell me . if that actually happened at a live show they would have my head. some of the singers don't like any form of disturbance while they sing. with the disks, one touch of the key change is instant and no sound is heard, even while the song is in progress.also the song never stops while playing for a beep of any kind with the disk player.mabe it's just the demo. i sure hope so with all the singers i have encountered in my travels i would be served for lunch......please advise, and thanx in advance...............:e :g