It’s possible the EQ needs servicing. It’s somewhat common and there are a couple of places around the US that can service/ rebuild them.
bose 901 and i pod
so I purchased the Yamaha as301 and the Audio engine b1 . They both worked well except for the Bose Equalizer which I am not getting any response from. .Music is flat .the slides on equalizer do not make any difference either way..
Cables are hooked up according to bose tape out to tape in . changing them makes no difference.
Any suggestions.