has anyone here ever experienced this problem?

have intermittent problem on only one TV channel, sometimes
reception is perfect, then reception will instantly degrade
to poor quality picture/snow/poor color, is VHF channel 6.
problem comes and goes. just annoying. started 2 months ago.

when reception instantly goes to poor, I can use the tuner
of a VCR and the picture is perfect when that channel is
viewed through channel 3 of the TV.

upon suspecting the TV tuner, I opened the shielded box
that the cable enters, the insides are only a bunch of
coils and what appears to be a crystal component.

TV is Akai CFT2791, have been looking for a schematic or
service manual to download online but have been unsuccessful.

akaiusa.com at one time had support for this TV on their
ws but apparently no longer.

any ideas would be appreciated.