Some issues with Panasonic HS860 stored in cold conditions

[Master Tape]

A few years ago i managed to snag a HS860 for really cheap because it was untested and stored in cold conditions for a long time (i think the seller said it was left stored in a garage) So the lid has these darkened spots all on it.

The machine itself plays perfectly fine but compared to my identical unit i noticed it has more chroma noise, the blacks look washed out (kind of greyish) and it doesn't look as sharp. Surprisingly it has very little comets compared to my main machine when you see text on screen (most notably on LP tapes)

Are these sort of problems caused by how it was stored, or do the heads just need a clean? Or is it more an electrical type issue (caps need replacing, ect)

[Sharc]

Cold (unless extreme cold) is usually less harmful than heat and high humidity and pollution. Also, you can't expect that 2 VCRs - even of the same model - will play the tape exactly the same ("analog" tolerances, different age and wear). I don't think dirty heads are the problem either - but we have not seen a sample capture and assume that the VCR settings (TBC, DNR) are identical for your comparison.
As a first step I would remove the cover and visually check for bulged or leaking electrolytic capacitors.


[Attachment 94067 - Click to enlarge]