The Kawai & Teisco Analog Synths Group

I seem to have the common problem of the 210 and 240 saving but not
verifying the cassette data. I used both small cassette recorder and a
4 track at various recording levels and always end up with no response
on verifying. The save functions properly and can hear the data
recorded, but when verifying, nothing happens. This is happening to
both synths, so I assume the odds are, I am doing something wrong!

any Idea what?