Don't know about the filter, but you might want to consider a notch eq or similar parametric eq. See if you can hone in on the offending frequencies & cut them dBs down to size. Probably down below 500 Hz.
The FASoft DirectX Parametric EQ plug-in has an AC compenstaion and a 60 Hz notch already built in and if youre in the line for an EQ anyway the price is certainly right at less than $20