There are many things that can go wrong and cause a pop. Since many DACs take a while to lock clocks just after an input change, sample rate change, PCM to DSD transition etc. they may hide a pop from upstream devices. In general DS users don’t want a fade down and back up at these transitions, so the DS software locks in a sample or two and you hear what’s coming from the source.
In each of the last three (or four?) releases I’ve tried to hide some of these pops (tho in general moderately well, sometimes it turned out pretty bad.)
The good news is that any such pop won’t be louder than the surrounding music. That’s because when DoP is played as PCM its volume is down at least about 48dB, so the transitions are the same as pausing PCM or unpausing PCM at the worst times with no ramps.