I have a DCS 50 that we installed an expansion cabinet on and now the customer is complaining of dropped calls and clicking on the lines, we removed the expansion cabinet and the call drops have stopped but the clicking is still present without the expansion cabinet it is clicking about every 30-45 seconds with the cabinet is increases to every 15-20 seconds and then drops the calls. The other strange part is that some of the calls will return on another extension as an intercom call going directly to speaker phone any help on this would be appreciated.

TIA
Don