PM9 Headphone jack

I posted a bit ago noting that I had grabbed a set of Planar Media 9s. Anyways, great speakers, especially for the price. But, with my Sennheiser 497s, there is a constant, never ending hiss. I can plug the headphones directly into my Audigy 2 and then there is no hiss but the Monsoon controller seems to have some sort of interference issue, I suspect, at least, since the only sources of interference I can figure are the video card (forced to be right next to the sound card due to this being a small form factor system) which is negated since plugging it into the card itself has no hiss or the LCD monitor, a Hitachi CML174SXW (which does have an integrated DC system instead of a 'brick'). But turning that off and unplugging it doesn't help, either.

Any ideas? Or is the volume controller on the PM9 just hissy, normally?

Thanks

I think the hiss is "normal" for the Monsoon volume controllers. I have the Planar Media 14s and there is a slight hiss I can notice when I plug in headphones into the headphone jack, a little bit more noticeable than the headphone jack on my old Harman/Kardon speakers.

You should have those headphones plugged into your soundcard anyways. That's the only way you'll get the best sound quality. If you want, grab a little 2 in 1 splitter at radio shack so your speakers and headphones can occupy the same input:)

Yeah...I realise that but the convenience... :/

I would like to use the headphones with other devices, too