I've been having a long standing problem with Windows 7 and Realtek HD audio (particularly on Acer Veriton's) and I've finally fixed it and thought I would share

The problem experienced is this. When logging into the machines (as anyone), by default the sound driver says that there is no audio equipment connected. If you plug in a set of headphones/speakers it then pops up a message saying device detected in headphone jack and then allows you to open audio files. The problem is that this only actually works best 3 times out of 10 The rest of the time it still doesn't recognize anything being plugged in and so students can't work on any audio files as part of their coursework.

After lots of searching I've discovered that Windows 7 has an auto-detect devices feature which clashes with the Realtek drivers auto-detect feature!

The fix is to disable Windows 7 detection so that it believes that audio equipment is always available The fix is a small registry edit:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l\Class\{4D36E96C-E325-11CE-BFC1-08002BE10318}\0000\Settings

Change the value of "ForceDisableJD" from hex 00 to FF

Then reboot. Hope that helps someone