[Elecraft] K2: Sound when switching off k2 after installing KIO2

[Michael van Hauten]

I installed a KIO in my new k2. All works well, all tests with the KIO installed passed without any problem. But: everytime when switching off the K2 i hear a short sound (sounds like "tscherp") in the speaker. With KIO removed, there is only a short klick at power down. 
Is there a problem or is this sound created from the KIO and normal behavior?

Michael, DC0ZO
K2#6614, K3#1999