Steve - I have had one switch fail - and it failed within minutes of installation (I'm not ruling out operator installation error, but I don't think that was the case since it worked initially, and then stopped dead. Martin (at AO) was kind enough to replace no questions asked).
Just confirming (you've probably already checked this) - make sure the little LED light is pushed in properly. You can disable UPB functionality by pulling that light out (just a little - maybe an 1/8"). When the light is out - the switch will still work locally, it just won't transmit or receive UPB information. Push it back in and UPB works again.
Just confirming (you've probably already checked this) - make sure the little LED light is pushed in properly. You can disable UPB functionality by pulling that light out (just a little - maybe an 1/8"). When the light is out - the switch will still work locally, it just won't transmit or receive UPB information. Push it back in and UPB works again.