My Metallica LE is having a strange problem that only shows every once in a while. When playing, the flippers go dead for a few seconds just like when somebody opens the coin door. It lasts a second or so, sometimes a few seconds, and you can continue with the next ball after that.

Somebody suggested recent Stern pinballs have a problem with the opto in the VUK of the ballthrough, but could that lead to dead flippers? I would think there was a problem with the coindoor circuit?

Any tips or similar experiences?

So it's a bit like the problem with eddy sensors on machines like RS and TOTAN? These also have connectors that have the tendency to deteriorate and cause problems. I solved these by soldering the wires straight on the connectors. Wouldn't that be better to do here as well? Apart from the fact that it's a bit sloppier than a Molex/header solution of course...