I have this same model.

If you heard something with SSB off, you should definetly hear
something with SSB on, regardless of where the tuning knob is. Mine
makes all kinds of crazy sci-fi space noise. Try tuning to a good
station (Like on normal AM), and then hit SSB. If you don't hear
anything there's prolly something wrong. You should at least hear the
pitch change or some noises when you adjust your fine tune knob.

Maybe what you're hearing is not SSB? For practice, I go into the ham
bands and try to find morse code which is in SSB. Somewhere around
3730.

Who knows, maybe my radio is just broke instead ...