The new pulseaudio version has been nothing but problems in my opinion. I do hope upstream recognize the issues and fix it by the next version.
You can create a temporary .asoundrc as previously mentioned. It will let PoL applications output to your specified hardware device without needing to go through pulse, which solves the problem. But it is not a good permanent solution. You could keep the .asoundrc in a different directory, and just move it into your home folder just before playing something from PoL.
The only other thing I can think of is to downgrade, provided you have not cleared your pacman cache.
Edit: In case it could be of interest. I also had problems with both Timidity and Munt, which is use to get great sound in old games running through DosBox. In order to fix this problem, I had to edit /etc/pulse/daemon.conf and add the line:
default-fragment-size-msec = 5
and then restart pulseaudio (pulseaudio -k && pulseaudio --start). Others mentioned on Arch forums that this also solved problems with crackling audio and other minor issues.
Edité par Daerandin