Hello all, I had a customer call to tell me their entire STS system was down first thing Monday Morning. I went into their office and at STA 100 the first thing I seen on the display was "Okay Sync" message and thats all. Their paging system which is connected to the STS was clicking. I took a voltage measurement of the battery inside and checked that I had a back up of the system prior to resetting the system. This got the phones out of the "OK Sync" message but once it did, they started freaking out. I would get handsfree calls from various stations, constant key tones through the speakers and CO lines would sound like pulse dialing. All the phones throughout the office were doing this by themselves. I Defaulted the system and still had the same issue. I removed all cards and put them in one by one, checking the slot config as I did. With the VM card, DTIB and LCOB with CIDU out the system will work but once I put any of those 3 in it will freak out. I have other customers with STS systems and would like to know if anyone else has come across this issue and what it may be. My customer with the issue is willing to upgrade their system since they have had it for a long time and are a little freaked out about how it was acting. Any input is appreciated.