Entertainment Center: TVs, Stereos, VCRs and DVDs - TV Reception

I have a 27" Pro-Scan. The coax from the cable company goes into a splitter, from which one cable goes directly to the TV and the other goes to the cable box and from there to the VCR. From the VCR there are separate audio and video cables going to the TV.
These last few days, the picture quality of most cable channels is very bad, some have no picture or sound at all, when the signal goes directly through the coax from the splitter to the TV. However, the same channels are much better when the signal goes through the cable box and VCR. This happens several hours of the day, the rest of the time the reception is the same.
Is the problem with my TV or is it with the cable company?

Remove the splitter from the equation and hook the COAX from the wall, to the cable box, cable box to tv. This will determine if it's the splitter. Splitters frequently go bad.

Also, why do you have one cable going from splitter to tv, and another one from splitter to cable box?

If it isn't the splitter, it might be the cable coming from outside. (The difference in picture quality between the TV & VCR could be because the cable box & VCR are amplifying a borderline signal better than the TV's tuner.)

I had a similar problem over the winter: Whenever the temp rose above freezing the signal would get noisy to the point where it was sometimes unwatchable. Turns out squirrels had eaten the insulation and moisture was getting inside the cable. Below 32 degrees the moisture in the line was frozen and wouldn't cause a problem. As soon as it thawed, the moisture caused a partial short and killed the signal.

HotinOKC wrote: "Also, why do you have one cable going from splitter to tv, and another one from splitter to cable box?"

Good question. If it's necessary to do this, the picture quality will be better if the cable box is connected to the VCR with A/V cables instead of coax. (That's one less modulator in the mix.)

Thanks for your informative comments. Today, the picture quality has been the same both ways so I didn't make any tests but wait until the problems appear again.
As for the splitter, my son hooked it up that way. I use the cable box and VCR not very often, so most of the time I just turn on the TV and select the channel.
I will let you know what I find out.