[Elecraft] [K3] Speaker output amp kaput

[Bill VanAlstyne W5WVO]

I recently fried (I believe) the speaker amplifier in my K3, apparently by 
just turning off the radio and turning it back on too quickly. Perhaps the 
fact that the AGC was disabled at the time might have had something to do 
with this, though that is just a guess. I accidentally turned off the K3 by 
pushing the POWER button by mistake, and, cursing my klutziness, immediately 
pushed the button again to turn it back on, as I was in the middle of a QSO. 
The radio came back on -- but sans speaker. It has been dead ever since. 
Configuration settings have been double-checked. It's not a catastrophe for 
me, because I normally use headphones anyway, but I'd like to get it fixed.

Since I'm not reading every post on the list these days, I have probably 
missed something about this, because I dimly recall seeing some subject 
headings about the speaker amplifier. I didn't read these. Is this a 
user-replaceable part? If so, what is involved?

And if this part is blowing up regularly, why is it so fragile? Is there 
something that can be done to better protect it?

My K3 was recently (couple months ago) updated at the factory with all 
applicable mods.

Bill W5WVO
New Mexico