Ive had a line also, looked like a streak you would see when a vcr tape is bad. Ive had my tv since last Friday, seen it one time, using HDMI1 with my Directv HR20 HDDVR.
Also about 5 times the sound just muted, dont know if its the tv or the Directv HDDVR.
Didnt have the mute icon, could hit volume up or down and didnt bring back the audio, had to cut off satellite and cut back on.
2 HR20-700 HD DVR
1 HR22-100 HD DVR
Samsung 40" LN-T4042H HDTV
Samsung 22" LN22A450 HDTV
Channel Master 4228 antenna
Greenville NC, Ral-Durham NC ota market