Playing any audio via spotify, youtube, BBC iplayer, XBMC causes the problem. The problem is the audio glitches, its never crashed, as I said the same device works flawlessly on a USB2.0 device amd has done for about two years. Even with no music playing the buffer level changes, the problem. I have seen this which is interesting https://forums.presonus.com/posts/list/33427.page I will try and get usbmon working tomorrow but it seems its a known Intel issue, I dont know if you can manage a software workaround. "Errata 1. USB Isoch In Transfer Error Issue Problem: If a USB full-speed inbound isochronous transaction with a packet length 190 bytes or greater is started near the end of a microframe the PCH may see more than 189 bytes in the next microframe. Implication: If the PCH sees more than 189 bytes for a microframe an error will be sent to software and the isochronous transfer will be lost. If a single data packet is lost no perceptible impact for the end user is expected. Note: Intel has only observed the issue in a synthetic test environment where precise control of packet scheduling is available, and has not observed this failure in its compatibility validation testing. * Isochronous traffic is periodic and cannot be retried thus it is considered good practice for software to schedule isochronous transactions to start at the beginning of a microframe. Known software solutions follow this practice. * To sensitize the system to the issue additional traffic such as other isochronous transactions or retries of asynchronous transactions would be required to push the inbound isochronous transaction to the end of the microframe. Workaround: None. Status: No Plan to Fix." On 31 March 2014 22:32, Felipe Balbi <balbi@xxxxxx> wrote: > On Mon, Mar 31, 2014 at 10:17:20PM +0200, Russel Hughes wrote: >> Hi, >> >> Thanks for replying. I can use a some USB audio devices, ones based >> around the Ti PCM2704 are fine, the DAC I want to use is called an >> audiolab MDAC and as I said it has an elasticity buffer, this sits at >> 50% full and is rock solid, as it should do, on USB 2.0 devices under >> Ubuntu 12.04 LTS fully patched ASRock 330 but not on the 12.04 LTS >> fully patched Intel NUC, where it reaches a maximum of 20% is highly >> erratic and drops out from time to time. The lsmod output is as > > you need to grab information of the error. lsusb alone doesn't provide a > lot of information (unless someone has dealt with the same error in a > NUC). > > Can you describe the actual problem ? How can you trigger it ? What are > you doing when the problem arises ? Do you hear audio glitches or does > the device disconnect ? Do you have a crash ? Does the *same* device > work on other setups ? > > Try to capture a usbmon trace of the failure, that's likely to help. > > -- > balbi -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
