Microsoft confirms the bug is caused by a software problem
Plenty of users have already reported a bug that causes the sound to be unexpectedly muted when using the Touch Cover on a Surface RT, with Microsoft always saying that it’s investigating the issue.While some users have managed to get their Touch Cover replaced, the Redmond-based technology giant has reportedly confirmed that it’s all because of a software glitch, so replacing the keyboard doesn’t make any difference.
“Replacing the Touch Cover didn't fix it for me. I called MS and apparently they have now been told it's a software issue and a patch is coming. The workaround they gave (until the patch comes out) is to always wake the Surface out of sleep mode by pressing a key as opposed to pressing on the touchpad,” one user said on Microsoft’s support forums.
The company is yet to announce a release date for the new patch, but expect it on the first Patch Tuesday cycle of 2013.