Hi,
I have Logitech HD Webcam 525 (046d:0826) but its mic works strange. The mic is turned off while video works fine. In dmesg I see the following messages
[ 472.079738] cannot submit urb (err = -18) [ 472.079748] cannot submit urb (err = -18) [ 472.079754] cannot submit urb (err = -18) [ 472.079759] cannot submit urb (err = -18) [ 472.079783] cannot submit urb (err = -18) [ 472.079787] cannot submit urb (err = -18) [ 472.079792] cannot submit urb (err = -18) [ 472.079797] cannot submit urb (err = -18)
I have did the following modifications to try to fix it (it works for some other cams)
add to the sound/usb/mixer.c case USB_ID(0x046d, 0x0826): /* HD Webcam c525 */
add to the sound/usb/quirks-table.h (see http://forums.gentoo.org/viewtopic-p-6886404.html) { .match_flags = USB_DEVICE_ID_MATCH_DEVICE | USB_DEVICE_ID_MATCH_INT_CLASS | USB_DEVICE_ID_MATCH_INT_SUBCLASS, .idVendor = 0x046d, .idProduct = 0x0826, .bInterfaceClass = USB_CLASS_AUDIO, .bInterfaceSubClass = USB_SUBCLASS_AUDIOCONTROL, .driver_info = (unsigned long) & (const struct snd_usb_audio_quirk) { .vendor_name = "Logitech, Inc.", .product_name = "HD Webcam C525", .ifnum = QUIRK_NO_INTERFACE } },
But all these don't fix the mic.
I have not enough experience to fix it myself but I can help with finding a bug and testing fixes. I have also found that the same problem exists for Logitech Webcam C310 (046d:081b). The bug is not specific for my laptop. I have the same issue on my desktop with both cameras.
See attachments for additional info.