I'm using Windows 7 Ultimate 64-bit and using the OpenMSX 0.3.1 music pack. Music plays fine for a few hours, but suddenly, it just stops playing any more music, and the sound effects from the game will appear delayed, or cut, or playing all at once or paused. However, the main problem is that while I still have OpenTTD or any other application running, which makes use of sound, like for example, Internet Explorer, or Windows Media Player, they will always play no sound, or come up with an error saying there's no win32 audio device available.
This sucks because sometimes it's a really bad timing to close OpenTTD, or the other applications. It looks like OpenTTD is hogging all sound resources to itself and thus prevents anything else on the system to play sounds. Sometimes not even closing OpenTTD fixs it, only restarting Windows will fix it.
The workaround I found so far is to never play any MIDI in OpenTTD, but that's to say I just want to prevent the bug to happen.
I'm using a somewhat complex/hybrid/licensed/whatever integrated audio device from my motherboard, ASUS Crosshair V Formula
http://www.asus.com/Motherboards/CROSSHAIR_V_FORMULA/#specifications
It's still a Realtek High Definition Audio but with those things licensed from Creative Labs, they call it then 'SupremeFX X-Fi 2 built-in 8-Channel High Definition Audio CODEC '
I have EAX, THX, ALchemy and TruStudio installed. There are a few issues with ALchemy and EAX together in some older games, but I managed to work this out and no longer have any issues, but I can't really find a way out with OpenTTD completely shutting down all sounds from the system.
The best clue I can give to you was some error from Windows when I was trying to mess with sound properties with its own tests saying that some other application is taking exclusive access to the DirectSound buffer and warned me that it could cause Windows to become unstable should I force Windows to play a testing sound.
What could that mean?