Kernel Panic in snd_complete_urb.

Issue

• When USB headset is attached to the system it hangs and then crash.
• Kernel Panic on USB Audio Disconnect.
• Call trace reads similar to:

BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8                 
IP: [<ffffffffa02a013b>] snd_complete_urb+0x6b/0xc0 [snd_usb_audio]
PGD 0 
Oops: 0000 [#1] SMP 
last sysfs file: /sys/devices/pci0000:00/0000:00:1a.1/usb4/4-2/4-2.1/4-2.1:1.0/sound/card1/uevent

Call Trace:
 <IRQ> 
 [<ffffffff813a6eb4>] usb_hcd_giveback_urb+0x64/0xe0
 [<ffffffff813cc886>] uhci_giveback_urb+0xb6/0x310
 [<ffffffff811544d5>] ? dma_pool_free+0x105/0x140
 [<ffffffff813cd275>] uhci_scan_schedule+0x3f5/0xb20
 [<ffffffff813cff2c>] uhci_irq+0x7c/0x180
 [<ffffffff8106090c>] ? run_rebalance_domains+0x4c/0x160
 [<ffffffff813a5d3f>] usb_hcd_irq+0x3f/0x90
 [<ffffffff810dbb60>] handle_IRQ_event+0x60/0x170
 [<ffffffff810de418>] handle_fasteoi_irq+0x88/0xf0
 [<ffffffff8100df09>] handle_irq+0x49/0xa0
 [<ffffffff8150635c>] do_IRQ+0x6c/0xf0
 [<ffffffff8100ba53>] ret_from_intr+0x0/0x11
 <EOI> 
 [<ffffffff812cddbe>] ? intel_idle+0xde/0x170
 [<ffffffff812cdda1>] ? intel_idle+0xc1/0x170
 [<ffffffff8109929d>] ? sched_clock_cpu+0xcd/0x110
 [<ffffffff81407c27>] cpuidle_idle_call+0xa7/0x140
 [<ffffffff81009e06>] cpu_idle+0xb6/0x110
 [<ffffffff814f754f>] start_secondary+0x22a/0x26d
Code: f0 0f b3 93 80 00 00 00 85 c0 75 64 48 8b 1c 24 4c 8b 64 24 08 4c 8b 6c 24 10 4c 8b 74 24 18 c9 c3 0f 1f 80 00 00 00 00 48 89 fa <49> 8b b6 a8 00 00 00 48 89 df ff 93 70 02 00 00 85 c0 75 ba f6 
RIP  [<ffffffffa02a013b>] snd_complete_urb+0x6b/0xc0 [snd_usb_audio]
 RSP <ffff880028263d18>
CR2: 00000000000000a8