[LAU] Missing master-volume on onboard soundcard?

Hi, there! Since approximately one year I have a new motherboard for my living- room-PC, called Biostar HiFi A88S3+. It's sound-device is a HDA-Intel with ALC892 Codec. I also use an "amplifier card" that is powered by the PCI-slot. With all of my recent equipment I've ever used it was possible to reduce noise that is produced by the digital devices in the PC: Lowering the master level did the trick. Just with the Biostar "HiFi" this doesn't seem to be possible. It always sounds like the master is open and all the noise comes quite audible through the speakers to my living room. Don't get me wrong: The master works. But it seems that lowering the volume is done by software. I wonder if this is a brand new method for manufacturers to save money or if probably the ALSA-driver is doing something wrong here? $ cat /proc/asound/cards  0 [HDMI           ]: HDA-Intel - HDA ATI HDMI                       HDA ATI HDMI at 0xfeb64000 irq 45  1 [Generic        ]: HDA-Intel - HD-Audio Generic                       HD-Audio Generic at 0xfeb60000 irq 16 Greets! Mitsch