I've looked through the forums and my problem seems to be different enough from other posts to warrant a new thread.
I'm running Mint 12, KDE. Yes, pulseaudio is installed and running.
I have a bottle set up just for Steam, and run TF2 through that bottle.
My problem is that TF2 will run perfectly for a random amount of time -- from 5 minutes to 20 minutes, after which the sound will suddenly stop working. I have yet to notice any particular event which causes the sound crash. Otherwise, the game continues to run normally, but without sound.
In the Steam browser, at the voice-test menu, I can still get sound while testing the microphone. Likewise, when I open Crossover's Wine Configuration dialog, the "Test Sound" button still generates the usual tone.
Sometimes logging out of my desktop, and back in again, will fix it. When it does, I'll usually lose the sound again more quickly the second time. More often, only a reboot will fix it.
The key bit of important information is that I had this problem under the old Crossover Games, but only when TF2 had been running for more than 3 or 4 hours. The original merge seems to have created the problem, which has become worse since the last upgrade. Now, since the last upgrade, the problem is chronic enough as to make TF2 almost unplayable.
Under Crossover Games, TF2 would share sound with other applications, such as a video playing in Firefox. After the upgrade, TF2 monopolized the sound. A video played in Firefox while TF2 is running, causes the video to stall, and Firefox to freeze. If I kill TF2, Firefox will unfreeze and the video will play. When I close Firefox and run TF2 again, it will have no sound.
As a result, since the upgrade, I have had to be very careful while playing TF2 to not allow any other program to access the soundcard. Under the original merge this was enough to get extended play out of TF2. But now it doesn't matter. I lose the sound fairly soon, no matter what I do.
I have not yet tried disabling Pulseaudio. I did find some scripts, through your forums, for turning pulse off and on. I'll try that next, and post my results here. In the meantime, if anyone has any good ideas, I will welcome the help.