Mark,

I didn't use a new pickup. The "original" is still up and running, it
just needed a new lens. To make sure that it has no other faults, I
swapped it with another one from a Sony-player I found laying around
in our workshop. The Sony played fine w/the Onkyo-pickup and the Onkyo
still showed the same behaviour. The DX uses a KSS210A while the Sony
is equipped w/a KSS150A. Should've mentioned that; shame on me.
Hopefully you've got another idea.

Best regards,
Lasse