Had this issue last spring with my Denecke PS-2. The DC input is a Tip/Sleeve 1/8" miniplug. When I first bought it the unit, I built an adapter for 9.6 RC batteries, and left the 1/8" plugged into the PS-2 at all times.
This lasted until the night of Roots Underground, had talked to the promoter, he spoke to band members and I had clearance to record. Opener was psyched to have a live recording too. Golden.
Plugged the battery into the adapter, red light. Low voltage, the battery had died. No problem, I'll disconnect the 1/8" and use the 9V battery compartment. Good taper me had a spare.
Went to pull out the connector and it was stuck. Opened the unit, worked it from multiple angles, stuck. Ended up having to break the socket to get the plug out. Put in the 9v and ready to go. Right? Wrong. About this time, the manager from the band came up to me and started yelling at me to tear down. By this point they had watched me hang my mics, I'd been there all sound check, and permission was pulled.
Still haven't had a space in my taping schedule to fix it. Now I have a homebrew adapter comprised of wood in the shape of a 9v battery with two screws at the terminal points, wires leading to my RC battery. If it fails, I can pull it and use a 9v battery. Eventually I'll replace the 1/8" socket with a locking dc connector.