Has anyone encountered problems with USB 2 outputs from a Mac? I am feeding my XDA2 from a mac Mini (late 2009) with everything set to 96/24. Using Amarra, Classics Online or Roon I get intermittent problems playing hi res tracks. The audio gets very jittery and unfocused with frequent pops.
There are a few posts here about problems with USB on a Mac - I tend to check in every now and then in the hope that some solution has been found. Fortunately, those USB problems are not the ones you describe! What you are describing sounds like what happens when another device -- a mobile phone/tablet, ereader, etc. -- is too close to my computer. I also see this problem sometimes when the furnace goes on (the furnace closet is in my office). Are any other USB ports in use when this happens? Another active USB port can sometimes cause problems as well.
Transport: Sony UBP-X700 UHD-Blu ray player spdif PC using Musiland Digital Times WASAPI via BNC connection - DAC: DC-1->XLR XPA-1 , RCA->Basx A-100 CD: Denon DCD 600 PCM 61 DAC. RCA Amp: XPA-1 gen 2 using XLR connections. Speakers: Axiom Audio m80 V3, Sennheisser HD700 headphones. two pairs 12 guage each bi-wire speaker cables per monoblock Headphone amp: Basx A-100 (INCREDIBLE VALUE!!)
Thanks for the suggestions but I think I found the cause elsewhere. FYI: I wasn't getting an externally generated signal--like the wacky morse code an iPhone occasionally broadcasts--but severe distortion of the digital audio.
The problem appears to lie within my old (2009) Mac Mini. It has USB 1 and USB 2 busses and periodically reassigns them to the USB ports. If the DAC ends up assigned to a USB 1 bus, the audio gets screwed up. Moving the connectors around and rescanning the ports will eventually reassign the DAC to a USB 2 bus. The only way I can find to prevent this from recurring is to leave the DAC on all the time so the Mac doesn't detect any changes in connected devices.