How to use and zzz(8) my uaudio

["Joel CARNAT" <joel%carnat.net@localhost>]

Hello,

I pluggued my Yamaha NX-U10 into my Eee PC to get a louder/cleaner sound.
When using the headphones jack, everything is perfectly all right.
Those speakers take electicity from USB. I never looked at it until I ran
zzz(8) and nothing happened. dmesg says:
uaudio0 at uhub1 port 1 configuration 1 interface 0: Burr-Brown from TI
USB Audio DAC, rev 1.10/1.00, addr 2
uaudio0: audio rev 1.00
audio2 at uaudio0: full duplex, independent
uhidev1 at uhub1 port 1 configuration 1 interface 2
uhidev1: Burr-Brown from TI USB Audio DAC, rev 1.10/1.00, addr 2, iclass 3/0
uhid0 at uhidev1: input=1, output=0, feature=0
acpi0: entering state 3
Devices without power management support: uaudio0
acpi0: aborting suspend

So, first question is, how can I put my laptop into sleep mode without
uplugging the usb speaker ?

Second question is, does uaudio creation mean I can use it to send sound
to it (rather than with the headphones jack) ? How do I do ? Just find the
application option that sets a specific audio device ?

TIA,
  Jo