Lusitanian,
It may be the way the signal is sent into the television, as noted by the support tech. I'm not sure why one television would do that, and not another, but if you can replicate the problem, you might consider having service come out and replace the tuner and any associated parts. You're under warranty, so the option is available.
The screen size may "change" when non 16x9 commercials come on, and appear that way. Or is the television screen size changing by itself?
The sound volume does change, and there's a lot of speculation on why - particularly when the volume blares during commercial breaks. I hear that across every brand, and every technology (LCD, plasma, CRT, etc), and that's the way the signal is broadcast. There are some volume stabilizers available at some electronics stores (like the Red "R" with the circle around it), but that's not an issue with the television - that is indeed a broadcast issue.
I wonder if the cable signal is doing something that enables signals to "reappear". I'm assuming you're not auto-programming the television each time. I don't have an explanation for that, so if someone would like to jump in, go for it.
--HDTech
I am having some issues with intermitent horizontal bars/lines showing up on the right side of the screen. I have called Samsung support and was told this was due to a poor signal from the cable company. My old Sony LCD TV never did that. I was also told this is due to the QAM Tuner on the Samsung. The problem usually occurs when a program switches to a commercial break. The bands normally disappear when it switches to another commercial or when it goes back to the program, but sometimes it takes a few tries. I know switching channels clears the up.
I also have an issue whereby the screen size keeps changing. I have it set for 16:9 format but sometimes certain channels change it to 4:3, even though I know it is being broadcast in HD on 16:9 format. Sometimes I apply the wide format mode to be able to better view the image. I can't figure out what triggers that one.
Lately it seems after programming the channels, somehow it adds the scrambled channels which is kind of annoying since I end up with a bunch of blank channels and have to click the remote numerous times when searching channels.
The sound volume is also not consistent from channel to channel. Seems HD channels usually have lower volume than digital or standard channels, but this is not always the case. The volume on some channels is really high to the point where I have to scramble to the remote to lower the volume.
Besides that, this TV has some impressive Picture Quality. Being a Technical Specialist involved with color, I do appreciate the quality.
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