USB TV device / usbaudio / loud hum

Hi!

When I try to use my new USB TV tuner (Pinnacle PCTV USB2 PAL) on Fedora 14 (log 
messages: in the end) 
with this:
mplayer -tv 
driver=v4l2:input=0:width=768:height=576:device=/dev/video2:norm=5:chanlist=europe-west:freq=224.25
 tv://

I hear nothing, but I c good pictures...

When I use this command simultaneously:
parec --device=alsa_input.hw_1 > bla.raw
I get correct audio with strong noise:
http://www.wgboome.de./bla.wav
(it is from input=1 for copyright reasons... so there is silence plus noise)

according to "amixer -c1"
(card 0 is the audio device on the mainboard and
is handled by pulseaudio)
the PCTV audio device has mono audio:
Simple mixer control 'Line',0
  Capabilities: cvolume cvolume-joined cswitch cswitch-joined penum
  Capture channels: Mono
  Limits: Capture 0 - 16
  Mono: Capture 8 [50%] [0.00dB] [on]

but arecord wants "-c2"...

someone on linux media mailing list thinks,