Problem with C-Media sound

Archived from groups: alt.comp.periphs.mainboard.gigabyte (More info?)

I've got Gigabyte GA-81915G PRO motherboard and on-board sound C-Media
9880.
Recently I installed TV Tuner AverMedia 303/403. Unfortunately I can't
hear any sound from my speakers. I checked TV Tuner's audio-out and
it's working properly. When I connect Tv Tuner's audio-out by cable to
Line-in (blue jack) I can't hear any sound from speakers connetcted to
Line-out (green jack).
After these adversities I connected Tape Player to Line-in (blue jack)
and I recorded sound without any problems. So, audio signal connected
to Line-in (blue jack) can't be played in Line-out (speakers).
Is it a motherboard defect ?? I installed newest drivers for C-Media
and for TV Tuner. I tried all changes in Xear3D program's
configuration.
It's weird for me that neither in configuration of mixer (Xear3D) nor
in configuration of Volume Control (Windows XP) there's no Line-in
option.