i am having an sony E series laptop.i have an HDMI port .at this stage ,i have tested my sound card , which provides audio out on my laptop i.e i could hear songs .my laptop has two sound cards amd 5450 and an intel-hda(alsamixer shows that as s/pdif)  . i decided to connect HDMI output to my new HD-TV.but, i could get only visuals on my TV,NO AUDIO OUTPUT ( HDMI cable works fine with win 7).my laptop has two sound cards.but i couldn't switch output to other card.( i don't know ,how to do that)
  i decided to update alsa. complied the following code in terminal.
    sudo apt-add-repository ppa:ubuntu-audio-dev/alsa-daily
    sudo apt-get update
    sudo apt-get install alsa-hda-dkms
then,strangely no login sound, and no audio output on my laptop at all .then, started complied code from step1 sound troubleshooting procedure from offical ubuntu site.then, my speaker icon taskbar disappeared .obivously
 $aplay -l
,provided output as no soundcards detected . so , i implemented step 4 from that guide, it provides a output of all hardware devices in my laptop.
    *-multimedia UNCLAIMED  
   description: Audio device
   product: Cedar HDMI Audio [Radeon HD 5400/6300 Series]
   vendor: Hynix Semiconductor (Hyundai Electronics)
   physical id: 0.1
   bus info: pci@0000:01:00.1
   version: 00
   width: 64 bits
   clock: 33MHz
   capabilities: pm pciexpress msi bus_master cap_list
   configuration: latency=0
   resources: memory:f0040000-f0043fff
   *-multimedia UNCLAIMED
   description: Audio device
   product: 5 Series/3400 Series Chipset High Definition Audio
   vendor: Intel Corporation
   physical id: 1b
   bus info: pci@0000:00:1b.0
   version: 05
   width: 64 bits
   clock: 33MHz
   capabilities: pm msi pciexpress bus_master cap_list
   configuration: latency=0
   resources: memory:f5e00000-f5e03fff
that command displayed output name of  the two cards . but , still i have no positive output on
  $aplay -l. so therfore, i think alsa couldn't detect my sound cards . is there solution to this problem? 
it could be better,if alsa would channel  output from multiple sound cards ?
how should install and configure alsa such that detects HDMI cable as soon i connect to my HD tv? is it possible to alsa and pluseaudio 2.0 to co-exist, if so how?