vista media player winupdate

Hi
I have just installed VISTA B2 Public Release on my desktop computer and I have encountered some problems which I never got in the previous beta builds and unless I can get these problems sorted out, I will be unistalling it for XP. I would like to know if anyone else has had these or similar problems and if so, what needs to be done to rectify the these annoying problems?
OK, VISTA installed fine and when I got to the desktop, Windows found a few updates for my computer, one was SoundMAX Integrated Digital Audio for my integrated sound card. ALL updates were installed without problems.
After rebooting, I heard the Windows logon sounds, so I knew that the sound was now working.
As the sound was working fine, I clicked on one of my MP3's tracks and Media Player v11.0 was opened and although it looked like it was playing in media player, there was no sound. My sound was turned up both on my speakers and media player, also in the master volume control, but still nothing was heard.
I then inserted an audion CD and launched media player, selected a track and clicked on PLAY, but again no sound was heard.
I found this really weird because in previous builds that I installed, MP3's and Audio CD's just worked, but now they don't. Anyone got any ideas on what's going on here?
I then decided to launch "MediaCenter" to try and play the default music content of Media Palyer 11 using the Media Center and it worked just fine, so I'm baffled as to what's going on here!
My computer has exactly the same hardware as before and nothing has been changed and what puzzles me is that I did not have these problems with previous BETA builds, so why am I getting them now?
Also windows update found around 9 updates after install and I installed those but after reboot, update found the same updates again andwanted to install them again and again.
The BETA2 Public Release should be a whole lot better than previous internal builds but from my experience here, it's not the case,
Intel 3.20E GHz 800MHz P4, 1.0GB PC3200 DDR RAM, ATI 9600 AGP Card 256MB DDR RAM, 2 x Maxtor 133 250GB 16MB Cache UDMA6 drives, 19" LG L1915S Flatron LCD Monitor.
Regards
Dave