Generally speaking, the Whistler (TRX1 & 2) will only stop on digital channel (control or otherwise) if it detects voice activity. In this way the user doesn't have to keep manually restarting the scan each time a data signal is present. The old MPT 1327 analogue was a right pain in the backside
Data transmissions cannot be decode anyway, so there's little point in the receiver stopping on them. With DMR at least, no human usable data is sent, so you won't get frequency, encryption key info etc even if you were able to decode it.