I have many tapes from the mid-70's onwards and always carry out a full FF & RW before using them for reasons mentioned here and to make sure the tape is complete and still fixed to the reels as I know nothing of the storage history of recently acquired tapes.
What I have found is that some of the pads (?) on the cassette tapes have lasted the duration, I suspect poor storage. Of the two distinct types of pad I have noticed, a few of the smaller, lighter coloured pads have become detached which is an easy fix as the pads are in good condition but, with the darker, larger pads, I have noted a few that have deteriorated and disintegrated (just as old foam may) and will need to be replaced with something suitable. I have my eyes peeled but suggestions are most welcome although salvage would be a last resort. (good examples shown below).
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