Quiet sound in movies from MP player (1 Viewer)

[gemini4all]

MediaPortal Version: MediaPortal 1.1.0 BETA 1
MediaPortal Skin: Default
Windows Version: 7
CPU Type: Atom dual core 1.6
HDD: 320gb
Memory: 2gb
Motherboard: Asrock ion
Video Card: Nvidia ion
Video Card Driver: Nvidia
Sound Card: Asrock ion
Sound Card AC3: Asrock ion
Sound Card Driver: Asrock ion
1. TV Card: N/A
MPEG2 Video Codec: ffdshow
MPEG2 Audio Codec: ffdshow
h.264 Video Codec: coreavc
Satelite/CableTV Provider: aster
HTPC Case: Asrock ion
Cooling: Asrock
Power Supply: Asrock
Remote: K100 compro
TV: Samsung LE40A656
TV - HTPC Connection: hdmi

I've got a problem with to quiet sound in movies when it comes to MP player. Codec is set to ffdshow, but it's quieter than playing the same movie for instance in KMPlayer - ffdshow codec is set for boosting sound - it works in KMP but not in MP. The sound is very quiet

Also it doesn't help to install AC3Filter - the same thing - quiet sound in MP

There is a way that is to chose MPC codec and to check "normalize" option in MP setting for MPC but some movies (maily MKV) are quietet in MP than in KMPlayer. Any ideas?