Why not a run high quality USB cable

Let's not forget that Larry_s has an async USB DAC, where the clock is not recovered from the input stream and transport and interface jitter don't exist.
Kijanki, your friend might still be OK, though, and the low price of the USB cable justifies at least a try. What other decent interconnects could one use for the same price?

Mihaitaa,

That's what I have (Benchmark DAC1) but I use Airport Express across the room instead of long cable, with 3' glass Toslink to DAC. AE has low (250ps) jitter, according to Stereophile measurements, that is further suppressed by Benchmark. My friend tried it a while ago but couldn't make it work. He returned it to Apple store and doesn't want to try again. It was most likely software setup issue.

Kijanki, I had the Benchmark and liked it, in general, but I found it to be far from jitter-immune. It responded to different transports and digital interconnects, which tells me that it didn't really knock out jitter.
It lowered it though, let's give credit where credit is due.
I bet that if you had a chance to listen to any asynchronous USB DAC you'll see what jitter-free really means and how wonderful computer audio can truly be. Throw in hi-res on top of that and you'll be thanking God for your ears, for without them your smile will go all-around your head ;-)