When I include any of my DT7500SN into the list of polled devices, my Vista 4140XMPT2 says **** DISARMED **** TEST ZONE then OPEN xx ZONE xx even though the zone is closed. This happens only with the DT7500SN all other polled devices operate correctly. The DT7500SN seems to work fine, it detect movement and if I try the auto learn function it senses the device and acquires the S/N correctly. Any idea? Thank you Leonardo