KPA500 s/n-1778 Factory assembled. This morning noticed the blank but lit LCD screen mid-ops. The amp.is working ok except for the blank screen. Amp. amplifies,switches bands etc;used with K3 None of the I/O ports connected. I see that this problem has been reported on the list but has gone off-line. Can anybody help.... Nandu VU2NKS...also ex-VU7AG