[Elecraft] Please Help - K2 Loss of SSB Transmit

[VK1OO]

Hi,

My K2 seems to have lost power out in SSB mode. As far as I can tell, 
the RX is still working OK in all modes. The inbuilt ATU seems to tune 
OK and there is power out in CW. When I hold the MH2 PTT in, there is no 
"click", but the RX goes silent, the RF/ALC display stays blank in both 
RF and ALC modes ie there are no bars when I speak or whistle into the mike.

Any suggestions would be appreciated.

Mike
VK1OO
K2: 2599