No picture or sound after connecting com cast cable box, helP!

SOURCE: Describe your Mitsubishi WS-65313 65 in.... Problem:

look for the CONVERGENCE settings either behind a small panel on the front or through the menu with the remote control

SOURCE: Help with my mitsubishi 65 inch tv

convergence ic going. you may also want to check some caps;
http://home.earthlink.net/~oleg.filippov/ConvergenceFix.htm
http://cmpalmer.blogspot.com/2006/11/fixing-my-own-tv-part-ii.html

caps
http://www.chrisandnat.com/Projects/BlinkingTV/blink.htm
http://www.jeremyburns.com/Mitsubishi-Green-Blinking-Light-Fix.pdf
http://www.fixya.com/howto/h159332-mitsubishi_dm_board_repair
http://hdtvoice.com/voice/showthread.php?t=32186
replace DM

SOURCE: HDMI to DVI cable connection picture problem

You are Just trusting on Monster Cable, thats what your doing wrong. HDMI and DVI are not same formates.

SOURCE: hitachi ultrascan HD tv 43 inch

Good Day;
If you don't hear the relay click suspect Q003. No power suspect Q912, Q914 & I901. Good Luck, big IRISH.

SOURCE: HDTV CABLE NOT HOOKED UP/WORKING

COMP 1 and 2 are for 480i/p sources. Hook it to the 1080i capable on the back. Also make sure the HD DVR is outputting 1080i not 720p. The Mits can not disply 720p and will show a scrambled screen if you try to.