Hi Guy, not had clamp issues before so please return them or photograph the cracked sections and I’ll replace them.
Yes the silencers do just slide on and a certain amount of condensate water will blow out. Most honda systems actually have a small hole at the bottom of the silencer to allow the escape of moisture.
To stop this you can remove the silencer and wipe a smear of black silicone onto the inserted pipe area. Refit and leave for 24 hours before restarting the motor and it should be fine.
Cheers.. Glenn