I'm sure the Grados are ok. but aren't they open backed?
I have found that sealed units are great for isolating pad noise if playing at lower levels.
Try some closed back Beyers.
I currently use a pair of AKG K271, which have a nice feature of cutting the audio to the drivers when removed from your head.
They also have a removable/replaceable lead and are supplied with bith vinyl and velevet pads.
Although expensive good prices can be found and they will last.
I will add a condradictory note that my 'HiFi' Sehns sound great too!!!
Matt
Never had a problem with pad noise and my Grados. Maybe I have the volume cranked too high.
A/V: Sony KDL-V40A12U & BDP-S350, BT Vision, Onkyo 875, B&W MT-30 7.1, QED A/V cables, R.A power cables
Hi-Fi: Arcam A85 & CD192, B&W 602S3 (& the PV1), Partington stands, Grado SR125, Kimber I/Cs, Rothwells, QED speaker cables, R.A power cables.