Sidechain input routing A4 to Rytm sync issues

Hi, when using the sidechain input routing possibility in OB to route the A4 mains to the Rytm mains everything syncs fine. However, doing it that way prevents the A4 sound from passing the compressor so I have tried routing it to the main fx L & R or any other track. Then the sound from the A4 passes the compressor but the sync is off.

Any ideas?