Solved:
I've replaced the OpenAL32.dll in"<home>\.gradle\caches\minecraft\net\minecraft\minecraft_natives\1.7.10" with a new one downloaded from the LWJGL site. I hope there aren't any incompatibilities that are yet to reveal themselves but so far sound works 100% of the time and there are no more crashes.
Original problem
I have minecraft crashing randomly while I try to make a mod.
It is not because of the mod as it happens even on a clean install.
I am using the recommended version of forge for minecraft 1.7.10 (forge-1.7.10-10.13.2.1291-src).
I tried deleting the gradle cache. Then unzipping the package to a new folder, running "gradlew setupDecompWorkspace --refresh-dependencies" until it gave no more errors.
Then running "gradlew eclipse".
So I guess it should be a clean install.
I then open the workspace in Eclipse and just press the "Run Client" button.
If the game starts and sound is working it doesn't appear to crash.
But if the game starts and the sound is not working (the majority of times) it randomly crashes once I load a world and walk arround.
Is the version listed as recommended problematic or is there something I am missing?
Thanks
Here is the output I get: