I have a really weird problem - first I noticed that the right arrow button had stopped working, but then after a while, it went into a very interesting failure mode - pushing the right button turns off the player hard - it goes totally dark and needs a power recycle to recover.

Any ideas?

Do you have any lights at all? (test light, strobe, LAN link integrity) My guess would be electrical (short or broken contact on the button) or software configuration / corruption (is the right button reprogrammed). Have you tried to reflash the kernel?

Make sure you don't have a loose screw rattling around in there!

I would suspect some kind of electrical short or break in the conductors in, on, or around the display board.

Well, it could be a crack on the display board (any drops in this unit's history?) or you are shorting to ground. I am not good enough with electronics to give you any more idea than that, but it sounds almost like a "self defense mechanism" (fuse?, PIC?) is shutting down to prevent damage.

It could be the MAX1631 power supply IC which in the Empeg, will reset at about 2 amps. It may act faster than the poly fuses on board, but it might also be what is tripping. What seems to be happening is that pressing the switch is shorting your 5 volt line to ground. The switch is normally not connected to 5 volts, but when depressed, it is connected through a 10K resistor network. The only way pressing the switch should cause such a fault would be if the resistor in the network became shorted for some reason.

With the Empeg off and the button fully depressed, measure the resistance between a grounded point in the Empeg and the 5 volt jumper. If you see a low reading of a few ohms, you have a problem. At this point you can release the button. If you find a problem, try measuring the resistance of each of the four resistors in the resistor network for the push buttons. Unfortunately, I believe these are behind the VFD next to the pad for the button LED resistor network. Again, if you find a low reading, you have a problem. Since you only mention one button causing this, only one of the four should have a low reading. If you find a faulty resistor element, try tracing it back to the push button. If it is indeed connected to the button giving you the problems, have the resistor replaced.

Hope this helps,
Stu

The resistors definitely hide behind the VFD. On a cursory measuring round, I didn't find anything abnormal. Will take closer look when I deal with the rotary encoders.

It sounds like a Right button jam - loosen off the left panel screws a quarter turn. Have you just put coloured buttons on?

No colored buttons, and it still happens even with front panel off and no caps on the switches.