I have this problem, even though I use the VST connect SE template!
I solve it by simply not bussing the playback audio. This channel is sent to the group channel (as per the template) so the performer can hear it OK for his vocals or drums and it is always sync’ed perfectly!
The only issue is that, as the engineer, all I can hear was what the performer is doing. Once a take is completed, all I have to do is route the playback audio through the stereo output and I can hear the mix.
I don’t think it is how this programme should work but it enables me to use it with no sync problems at all!
If there is no other solution I hope this helps!
EDIT I am using the system wirelessly, with a 1 second delay setting!
Jim B