M17xR4 Sound Muted

Hello all,

I have only had this problem for a couple of weeks now. When I boot up and log into WIndows (on battery power only), the sound icon in the systray is muted. There is nothing I can do setting-wise to enable sound. However, when I boot up and log into Windows when connected to the AC power, the sound is fine and the icon is not muted. I have tried updating the Bios, the sound drivers (Device Manager shows 'High Definition Audio Device' and 'Sound Blaster Recon3Di' fine), and the Chip-set drivers. I do not have another battery to swap out to test further.

Has anyone come across this issue before? Thanks in advance

 

I went to the power options and put all the settings into high performance...still a nogo. Also, I have tried (AlienRespawn) to factory image...still same problem exists. The issue is also present in safe mode. I also tried draining the power from the computer and cleared the BIOS/CMOS by resetting the CMOS battery. BIOS is at A12. Again, the problem is only when powered by the battery...with the AC adapter, all works fine.

I just found a post in Dell's forums with this exact issue. Looks like no one was able to figure it out without getting a motherboard replacement:
http://en.community.dell.com/owners-club/alienware/f/3746/t/19456561.aspx?pi21932=5

This is a real bummer since my warranty ran out at the end of last year.

 

Additional notes:
If I hover over the sound icon in the systray, it says 'no audio output device is installed'. 'Device Manager' now shows 'Intel Display Audio' under the 'Sound, video and game controllers' drop down instead of 'High Definition Audio Device' and 'Sound Blaster Recon3Di'.

If I click on the sound icon, I get a prompt with title that says 'Playing Audio'. Then, below, it says 'Detecting Problems' and says 'Troubleshooting could not identify the problem'. I viewed the detailed information and it says ' Potential issues: Check Audio Device - there might be a problem with your audio device and also says 'One or more audio service isn't running'. The type of audio device being diagnosed: 'Endpoint' Speakers, Headphones, Headset Earphone'. If I go into 'Computer Management', under the 'Services', nothing is listed relating to sound or audio.

If I Open the Sound properties (Manage Audio Devices), the playback and recording tabs say no audio devices are installed. Under the 'Sounds tab, it shows all of the sound wavs that can be changed in Windows like normal but when any sounds are selected, the test button is greyed out and so nothing can be tested. If I plug in headphones, speakers or SPDIF, nothing happens...no audio comes out and there is no messages displayed on the screen.

Again, if I reboot with the AC power, all is fine and there is no red X on the sound icon. Sound comes from the speakers, headphones, and SPDIF fine.