Windows 7 goes in stand-by (1 Viewer)

[Nachtfalke41]

MediaPortal Version: 1.1.1
MediaPortal Skin:
Windows Version: Windows 7
CPU Type: AMD 415e
HDD: WD Caviar Green 1TB
Memory: G.Skill 2x2 GB
Motherboard: ASUS M4A88DT-M/USB
Video Card:
Video Card Driver:
Sound Card:
Sound Card AC3:
Sound Card Driver:
1. TV Card:
1. TV Card Type:
1. TV Card Driver:
2. TV Card:
2. TV Card Type:
2. TV Card Driver:
3. TV Card:
3. TV Card Type:
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec:
MPEG2 Audio Codec:
h.264 Video Codec:
Satelite/CableTV Provider:
HTPC Case:
Cooling:
Power Supply:
Remote:
TV:
TV - HTPC Connection:

Hello,

Windows goes in stand-by, when i am hearing music.
Any ideas?

Andi