AC noise on DC effect stepper drivers?

My dad turned up something investigating our lost step problems and I
wondered if anyone knows if the following can be a problem:

Dad remembered that some full wave bridge rectifiers can leak AC into
the DC output. He checked and found 43vac on top of the 43vdc we're
getting out of our unregulated power supply.
The power supply was built from schematics supplied with some CyberPak
drivers I was using and consists of a transformer, capacitor, full wave
rectifier, and bleed resistor for the cap.

Can this AC be causing occasional lost steps? And even if not, is it
something we really ought to filter out? (I'm assuming yes, but thought
I'd ask)

Thanks,

Jon Anderson