Yes, I had the same trouble with live piano sound on YouTube.  Digital
camera microphones are no good; even the hotshoe mic renders a horrible
sounding piano.  The best and cheapest camcorder I came up with is the
Canon HG10.  It makes video at 1080 HD, and you must have an external
mic input.  So I plugged in my 30+ year old Radio Shack 1080 mics, and
the system worked perfectly for a few days.  Then one mic got sick; the
output was only 50%. Some of my early video's have unbalanced sound.

Now I am using a pair of Nady SPC-25 battery-powered mono mics, using
the same 3-pin XLR cables from the Radio Shack mics.  Plug the male XLR
ends into a 1/8 stereo adapter that has a single 1/8 male output.  Plug
that into a cheap Radio Shack volume adjuster (like used on headphones)
that has an L-shaped plug to go to the mic input on the camera.  Take
short one-minute trial-and-error videos, cutting down on the mics'
volume till that piano sounds great. 

To check out my videos on YouTube, just type "pianmn199" and hit enter.

John Taber
East Hartford, CT

 [ http://www.youtube.com/results?search_query=pianmn199