Quoted from Flynnyfalcon:

Quoted from Flynnyfalcon:
What would cause some sounds to disappear from a Classic Stern? The end of game sounds on my Quicksilver have vanished (and possibly one of two others). I thought it was cable issues (and it still might be), but after giving them the once over, everything appears to be working ok, except the end of game sequence sounds. Any thoughts on how/why it would happen?

Just following up on this for anyone suffering similar issues. It turned out a few of the ICs had failed on the sound board, namely a 4081, 4053 and a 4516. All replaced and working again