About 16-17 miles away, same group different branch. I’ve asked on the FB group if there’s anyone near Durham with the Canton system I can go listen to, just to make 100% certain I’m not going mad or my ears have stopped working properly!. I even gave my home HiFi a good blast this morning to make sure (waited until the cat had gone out!), the bass from that rattles my doors and windows even without a subwoofer (Kef 104AB’s)
Do you have a wooden brush handle?
If so put one end where the sub is located and the other tightly to your hear, block your other hear with cotton wool or your finger and focus on what comes from the sub.