On Sat, Oct 9, 2010 at 2:55 AM, Geoff Beasley <geoff(a)laughingboyrecords.com> wrote: Hi, Geoff, thanks for answering. Clemens is perhaps the ultimate USB audio guru, but everyone else's experience in this issue is of course valuable and appreciated. I tried this on Ubuntu and Fedora Core stock kernels (no -rt patch). On Ubuntu jackd simply failed with no clue about was going on; Fedora's kernel at least supplied the message I quoted in the top message (probably it has activated some debugging flag that Ubuntu's doesn't.) If it helps some (probably not, since all the hubs in the market will be some kind of wrapper or another around the same Taiwanese chip), the hub model is Manhattan 160612: http://komputercenter.com/usb-gadgets-c-7/hub-usb-2-0-manhattan-160612-p-16 Has someone else here managed to successfully run jack over USB audio through an external hub? It is probably not the best setup out there latency-wise (how long does it actually take for a USB frame to pass across a hub, anyway?), but may be worth considering if low latency is not critical, providing in return integrated USB port protection and perhaps some degree of power supply noise isolation (or yet another noise source, you never know, but I'd hazard the guess that anything that separates audio equipment from LCD inverters in laptops should be a good thing.) Cheers, L