[Elecraft] K2 deaf on CW

[k8rs]

Here is the problem: 
                        
      My K2/100 performs very well on USB and LSB, but it nearly deaf on CW.   I have used it mainly as a platform for transverters on 2m, 432 and 903 and was not aware of the CW issue until this January during the ARRL VHF Sweepstakes.  I had many 903 contacts that were so weak that I needed CW.  Even with the CW filter set to the widest bandwidth, I could barely hear and ended up finding them via SSB mode.  A test on 40M showed me that I do indeed have a problem.   What gives here?  Output is fine in all modes  SSB is fine in receive in LSB and USB.  Only CW seems poor and on receive only. I have some ideas, but would like to get some input from the Elecraft group.
                  Thanks in advance.
                                              Roger K8RS