Welcome back. A quick update on the repair of the Behringer Ultracoustic ACX900:
One of the failed components on the Behringer was the switched 3-pole jack input on channel 2 which, being plastic, had sheared off at the base of the threaded bit. Our replacement (below) has a metal socket instead of a plastic one. Why this hadn't been fitted in the first place is a secret known only to Behringer. After all, channel 1 has a metal jack so why not channel 2?