[Elecraft] K3 Speaker is mute

[Alex “PY2SEX” PYtwoSEX]

Hi all,
First post after couple of years. Recently I’ve put my K3 back to my bench but I noticed that speaker is mute. It wasn’t before and after search for the issue, I found something regarding the protection of mono plugs connected at back of the radio, is that the case?
I connected only a DB37 for the microham and my headset was in. After I removed the headset, no sound.
If I connect my headset at front or back everything is fine, only the internal speaker is completely mute.
Any tip or idea?
Thanks in advance.

73
Alex
PY1KS | PY2SEX | DL1NX | CT7ANB | PA/PY2SEX | AC1CY
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