4 wire smokes and polarity reversing relay

I have a polarity reversing relay for my 4 wire smokes.  The relay is set up as a siren on board #1, and it's set to trigger when the smoke alarm zone is tripped (zone 8).  The problem is that when the alarm is dismissed, the polarity reverser continues to alarm until manually switched off.

I thought when you dismissed the alarm, and the smoke detector that tripped is cleared, the siren should be switched off.  

Anyone have experience with this?

Thanks,

Jim