What threw me off also is that the K1 has actually better audio "oomph" than the K2, so the signal sounded more powerful, or fuller.
I wanted more audio out of my K2 also.
The speaker audio is fine, but not the headphones.
Since I use headphones %99 of the time, I changed
the values of those two resistors that are behind the
headphone jack. Sorry, can't remember their numbers
or the value I changed them to at the moment.
Elecraft Tech Support can help you there, they
gave me the info.
And just for grins I tried the Receive Preamp Mod
listed at their web site. (Or at least it used to be).
Just change the resistor R76 associated with the
2N5109 transistor on the bottom of the main board.
I changed it from the stock 10 ohms to 6.8 ohms,
using a %2 tolerance resistor. It gives the preamp
a bit more gain and I noticed no negative changes
in selectivity. The preamp was working fine, I just
wanted to try out the mod and liked it.
Good luck and have fun with your K2.It really is an amazing rig.....
and you can fix it yourself!
73, Ken AD6KA