Hi Alan, A bug was opened against the Ubuntu distro[0]. It is believed that the following commits introduced the regression: commit c44b225077bb1fb25ed5cd5c4f226897b91bedd4 Author: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Date: Mon Oct 1 10:32:09 2012 -0400 UHCI: implement new semantics for URB_ISO_ASAP commit 6a41b4d3fe8cd4cc95181516fc6fba7b1747a27c Author: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Date: Mon Oct 1 10:32:15 2012 -0400 OHCI: implement new semantics for URB_ISO_ASAP The regression was introduced as of v3.8-rc1. I see the following commit was created to address a similar issue to this: commit e1944017839d7dfbf7329fac4bdec8b4050edf5e Author: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Date: Tue May 14 13:57:19 2013 -0400 USB: fix latency in uhci-hcd and ohci-hcd I created a test kernel with commit e1944017839d7dfbf7329fac4bdec8b4050edf5e. However, folks affected state this bug still exists with commit e194401. It is also reported that this bug exists in the latest Mainline kernel. I see that you are the author of these patches, so I wanted to get your opinion on the issue. Thanks, Joe [0] http://pad.lv/1191603 -- 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