Thanks
@rayl and
@Jawed ! Sadly Jawed the link to the 10 ferrite core packs do not ship to the U.S. Though the USB Cable does. Will definitely look more into this. Seems like a good way to get rid of RF noise and other interferences at a cheap cost.
The USB cable is by an American company so you'll find that on Amazon.com. The ferrites are also on Amazon.com:
https://www.amazon.com/dp/B01E6PLXXC
The 5mm ferrites (which I use) do fit on the TrippLite cable but it's a very tight fit (causes sore fingers). So that's why I recommend 7mm inner diameter.
If you find there's an improvement with this setup, then buy another 20 ferrites and then just forget about any more tweaking. The key here is that lots of them work better than just a few.
I also use the twin Jitterbug setup that Audioquest recommends. Lots of ferrites were a vastly greater improvement than the Jitterbugs.
If you can connect just an optical cable to your DAVE (unplug all other digital sources you might have) this will give you the reference sound quality for your USB tweaking.
When you buy ferrites from Amazon it's a lucky dip, because the filtering characteristics are unknown. But no one has identified the best filtering characteristics for ferrites that go on a USB cable, so what can you do? Worse, when you do find the characteristics the data presented cuts off usually at very low frequencies like 100MHz.
Theoretically a mixture of ferrites is best to attack various frequency ranges, e.g. 100MHz and 1GHz. The 1GHz ferrites should be placed closer to DAVE than the 100MHz ones. Alternatively, just put a ridiculous number of them on your cable. It's not as if you'll be wearing the cable like a necklace, so it really doesn't matter if it looks strange. A longer USB cable is actually an advantage, since it will allow you to put a ridiculous number of ferrites on the cable. (I actually have 66 on the Tripp Lite cable, including the 2 that are built in, covering the entire length, just because I can.)
Fair-Rite is the most famous company that makes ferrites as far as I can tell and the range of products is huge. You can buy these on Amazon, e.g. here's one:
https://www.amazon.com/dp/B005S45EWC
Very expensive, but in theory you know the characteristics. If you're feeling adventurous you can buy a large variety and then do listening tests to work out which ferrite characteristics are the best. I suspect 1GHz+ is preferable and there's not much choice of those, so it's up to you how tweaky you want to be. Specialist electronics suppliers should be a lot cheaper for Fair-Rite. Würth is another company that you could investigate.
I went for the brute force solution instead, which happens to sound the same as optical, i.e. it does exactly what I want.
Now playing: Dire Straits - Why Worry