sony sacd 777--acting odd--what's going on??????

my sony sacd 777 has been left on and in almost daily use for over two years. during the last few months off and on i experience the following:
-high pitched noises after the door closes while the 777 is proccessing prior to playing music
-it mistracks more often than before. this occurs maybe an average of twice per week. turning the unit off and on usually take care of it. the slightest dirt or finger prints must be cleaned off the cds or the machine will mistrack.
by mistracking i mean that either the cd will not play at all----display says "no disc" or less often it does the old cd skip.ie the same tone repeats continually
-i can live w/ occassional minor problems, but i've read about the standard sled motor and spindle motor problem that these sonys have and need more info. is it time to send it in for service. with a problem that doesn't occur most of the time i use the unit, i'm afraid that the service dept personel will miss the problem and do nothing.
WOULD 777 owners tell me what's GOING ON WITH MY 777???
PLEASE!!!!! WHAT'S THE BEST WAY TO HANDLE THESE PROBLEMS AT THIS POINT? I DO HAVE A FIVE YEAR WAR?

THANKS FOR YOUR HELP IN ADVANCE!
BOB FROM MIAMI, FL

PS. THE VPI SCOUT & CLEARAUDIO VIRTUOSO ARE ON THEIR WAY TO KEEP ME SANE DURING SERVICE TIME--AND MAYBE EVEN MODs---ONCE I'M READY FOR ANOTHER TWO YEARS OF BLISS W/O PROBLEMS!