one sound channel whoes

hi,

I updated current last monday, and this day too.
one sound channel whoes.

I don't think it is a driver issue, because the oss driver
gives the same result.

of course i verified:
  - cables,
  - sound output (only 2 channels)
  - amplifier and so on.

  - FreeBSD 6.0 works fine!

it is an asus pc-dl deluxe card with
ich(5), bi-xeon.

any idea wuokd help.

tahnks

   raoul
   rmgls_at_wanadoo.fr