XBMC Buntu Dissapointment

So I dual booted Windows 8 with XBMC Buntu. I'm using a VGA cable and get 1920 X 1080 at 60Hz connected to my Samsung 46 inch. The computer has a DVI to VGA adapter an then I use a VGA cable to TV. Maybe I'll get better picture using HDMI cable or upgrading my Graphics Card. However that's not my problem.

My problem is when I'm using XBMC Buntu, I'm using a 3.5mm jack to connect Audio Out from Computer to the corresponding Line-In matching my TV input. The sound is LOW. However when I switched to Windows 8 and watch YouTube, the sound is perfect. So just for the heck of it I installed XBMC into Windows 8. No problem there AND my Sound is MUCH IMPROVED.

So bottom line is I expected to normally boot my Media Center PC in XBMCBuntu and rarely in Windows 8. However, right now, I cannot watch any movies by directly booting into XBMC because of sound issue. There is not much to play with the settings and I've tried pretty much everything.

So why does XBMC within Windows 8 sound so much better than within XBMC Buntu? Is it a driver issue?

PS Wanted to add, with Windows 8 I'm using Eden (11) while with XBMC Buntu I'm using Frodo (12) Beta 2. But please don't tell me that's the issue.