There's a value in the scanner under expert setting that are called Digital Detect Time. If it's anything like in a Uniden scanner it is a timer that mutes the audio for a while until the scanner have decided if it is a datasignal it can decode and then outputs decoded audio or just unmute the raw audio for an analog conventional signal.
I always have that value set to zero so that I can hear if it's a datasignal I hit and it will mute that data after some 300mS and then switch to decoded audio, or instantly give me the audio from a conventional transmission. I don't like any kind of delays in the audio and I prefere to hear the initial data burst but some people might like to have it muted and accept the delay of the SQ unmute.
It is set to mute for 600mS after a squelch detect as default in the PSR600. The Whistler TRX doesn't have that as a user setting and are only one of several unexplainable anomalies in the TRX firmware. New doesn't always mean better and improved.
/Ubbe