I've been having a lot of trouble with my cable and I can't determine where the problem is (my tv, or the cable company). I apologize if this gets long winded but I wanted to make sure I get all of the details.
I currently have limited basic cable with Comcast. I made the change to limited basic earlier in the year. It was working out well for me because I was receiving local HD through my DTV port on my Vizio VX37L. A few month ago a ran into an issue where those stations stopped coming in. When I would tune to one of them, I would get a blue screen and it said "No Audio or Video". I would do a channel re-scan and still had the same results.
Around this same time, Comcast in my area went all digital. Suddenly I was also having lots of trouble completing a scan on my TV. It will almost never complete a scan, always getting stuck on 37%. I did some research on this issue and found some results. However, all of the solutions haven't really helped (I even called vizio and they ran me through the same solutions, which oddly enough worked that time, but failed to work consistently since). So anyway, if the stars align and I am able to complete the scan, the stations are still blue with the no audio or video message.
There are, however, some stations that do come in- about two QVC ones, and TBS. This partly has me believe it is not an issue with the TV, like a busted tuner, because I am getting at less one or two stations. But then I wonder why I am having some much trouble completing the scans. It has gotten nearly impossible to complete them (today I was able to after weeks of trying at least a few times every few days).
I have also tried contacting Comcast on this many times and they really don't know what I am talking about. I did some research online and it seemed like an issue could be with Comcast moving the clear qam channels around as someone said:
Comcast may have relocated the channels to frequencies which are blocked by a previously installed filter. You may find the new frequencies by checking at this site -- the filters were installed to prevent theft of services when the channels were analog, so Comcast may be willing to remove them now.
I tried to explain this a few times to Comcast and they said they would pass it along to the engineers but I never heard anything and it obviously still isn't working.
The third wrinkle in all of this that I feel is worth mentioning is that with the digital transition, Comcast states that if you have an HDTV with a digital tuner, you will not need to have a DTA adapter on that TV. However, this does not seem to be the case as if I tried to just go straight from wall to tv, I get the message on the screen saying that if I see this I need to get a DTA.
So this is where I am stuck. If the issue is with my TV, then I don't want to fight with Comcast on this issue. I have been resistant to them sending someone out here because of the scanning issue. If the tech comes and we try to do a channel scan and it gets stuck, then he is going to say it is the TV's problem and they will charge me for coming out.
But could it be that my TV is getting stuck on the scan because of the Comcast system? If they really changed things around with the digital transition and the clear qam, then could my TV just be having trouble processing the channels?
Again, I really apologize that was so long, but I felt it was best to explain as much as I could. Unfortunately I don't have another HDTV here to see if it works to help determine if it is my TV or not. I really appreciate any help anyone can give.