When you mention squelch chirp, it only happens at the end of conversations when a user stops transmitting?
The SDS100 handles the analog audio in a digital way and it will be delayed some 100-200mS but the squelch function have no delay so it will clip off the last 100-200mS from the audio and remove the squelch tail. Sometimes at the start of transmisisions it will create a bit of a chirp or similar sound in the audio that could come from unmuting too early. But that's at the start of transmissions.
/Ubbe