Since applying the December updates (including firmware) the battery continues to drain after I stop using my Surface Pro 2.
I ran powercfg /energy and discovered that the likely culprit is my Touch Cover (version 1). Without the Touch Cover attached, I get no errors. With the Touch Cover attached, I get 2:
System Availability Requests:System Required Request
The device or driver has made a request to prevent the system from automatically entering sleep.
|
Requesting Driver Instance |
HDAUDIO\FUNC_01&VEN_10EC&DEV_0280&SUBSYS_10EC104E&REV_1000\4&2aee3be3&0&0001 |
|
Requesting Driver Device |
Realtek High Definition Audio |
USB Suspend:USB Device not Entering Selective Suspend
This device did not enter the USB Selective Suspend state. Processor power management may be prevented when this USB device is not in the Selective Suspend state. Note that this issue will not prevent the system from sleeping.
|
Device Name |
USB Composite Device |
|
Host Controller ID |
PCI\VEN_8086&DEV_9C31 |
|
Host Controller Location |
PCI bus 0, device 20, function 0 |
|
Device ID |
USB\VID_045E&PID_079A |
|
Port Path |
3 |
The USB device above is the Touch Cover. It seems to me that the audio control portion of the Touch Cover is interacting badly with the audio driver. This seems to prevent the Surface Pro from automatically entering sleep mode.
Before the December firmware update, I did not notice any unusual battery drain. One thing to note is that before the December firmware update, my Touch Cover Telemetry driver could not be installed. Applying the firmware update fixed that issue but caused this one.
I do not have any unknown devices in Device Manager. All my drivers appear to be up to date. There are no errors or warnings showing up in the Device Manager. All updates have been applied. I have not attempted any fixes to any of my pre or post firmware upgrade issues other than allowing Windows Update to do its thing. Also, please note that this is the original Touch Cover, NOT the Touch Cover 2.
