Which remote do you suggest?
I got an apple genuine remote. Works fine but it may not work straight out of the packet. Mine didn't.
There is a sequence you can use to change the code on the new ones to switch between the various apple remote versions, but for the life of me I cannot remember it. Dave may have it tucked away somewhere.
I bought a few from ebay and the cheaper plastic ones can sometimes have problems with the battery holder making bad contact. The more expensive metal ones seem to be reliable but smaller to handle. Both should work with the Preamp straight out of the box but there might be some setup procedure to change modes.
Happened again today.
Just kept pressing buttons and hitting the MENU button to see if it would power up the UP.
Press and hold the MENU button and the RIGHT button TOGETHER for 6 seconds or a bit longer. Keep doing that and see if the UP powers on.
Should work. Worked for me.