I'm getting little scratchy data noises across my soundcard. Anybody know a way to filter them? Grounding strap? What?

It seems to be my wireless card. I was watching a stream earlier and it was scritch scratching away. Thought my headphones were blown. I wonder if moving it to a new PCI slot will do anything...?

You don't give much information - what is your card, what do you use to monitor those noises, etc.
For example front mic and phones jacks are famous for being very noisy. There is simple mod for that and now my cube PC is totaly clean and dry on the front outputs!
I've also tried to capture audio with the onboard sound card (Realtek ALC650) of a modern Intel based MoBo. Compared to USB interface (Onkyo) it was a bit noisier and a bit less defined and crisp but that's after direct comparison. If I had only the onboard recorded sound I wouldn't say it sound bad - it was perfectly intact - no cracks, no noise - even made CD out of it!

So please tell us what exactly is your set up.