Well, that is weird!
When weve installed 1.15 it seems that sound and music was turned off by default. Every test to turn either music or sound on crashs the client!
Reproducable every time for every of our members: Start client, goto options, try to turn music/sound on, crash.
Edit: This fix brought the sound back but it seems no IC sounds: http://player.to/ic2_20111003_v115/soundsystem_update.zip
Edit2: Machine sounds needed a while but its there with that fix! Enjoy!
I have been playing with no sounds for a while but then got bored and then that is when I noticed the crashes which then started to annoy me knowing something is broke and also playing def so to say. This fix worked perfectly even though it doesn't have IC2 sounds I can live without that.