[Elecraft] K3 LEDs light up, but won't come to life

[Eric Rosenberg]

thi has happened three times:

I turn on the K3, the LEDs on the four knobs under the display light up, but
the display stays dark and I cannot power it off with the power button.

I have to disconnect the power, wait a little bit and re-connect the radio.
It comes back to life when I power it on.

What's happening?

Eric W3DQ
Washington, DC