Sound problem

Hi,

I install Windows Vista on my computer and I've problem with sound.
Sounddriver is Intel(r) 82801 DB/DBM AC '97.

Sound-out is in pink jack (before this time was microphone). When I join
passive headphones, is sound OK, but when I join active repro, I hear hum.

What can I do? Can you help me anybody?

I thing, I must install SoundMAX or similar software for selecting output
and input jacks, but I don't know which?


Thanks for your answers


Sokolik