Windows 7: Odd audio problem since Win 7 install

I have an odd problem with Windows 7. When the PC boots the audio does not work. If I look at the audio setting everything looks good and you can see the audio level meter bouncing up and down.

After playing around with various options to no effect I finally tried re-seating the 3.5mm jack that feeds the amp and audio made good. So I thought at that point the jack had come lose. However next time I rebooted my PC it was mute again, re-seat jack and it's back!

I have had this PC and amp setup running fine on Vista for the last 8 months. It's only since installing (Clean install) Win 7 that these problems have occurred.

do you have realtek hd audio manager ?

I have an ASUS P5E motherboard and use the on-board soundcard this is an SupremeFX II 8-channel HD codec: ADI AD1988B.

Is the Realtek audio manager software?

kind of, realtek is the sound card on my pc and has realtek drivers, the audio manager allows you to configure the rear speaker jacks and choose the sound settings you want ie club ,lounge,bathroom etc i just wondered as my install reset the check box in audio manager which cut the sound to my amp, if you had realtek sound then i had poss solution

It seems that there is nothing coming out of the audio port till the jack is removed and replaced after each boot. It's as if this maneuver kicks the sound-card into life somehow. Very very strange.

Its probably something to do with the drivers for your audio card.
I have an Asus M2N-MX, nForce 430 chip set I believe, and when I used certain soundMax driver/manager programs, it would constantly spam messages saying the jack has been plugged in, and then that it was unplugged. Even on the microphone port, which has nothing plugged into it. Its clearly the driver/software.