Your ignorance is the Devil's bliss. Every time you scorn what confounds you, he smiles. Every time you sow the fear of him where there was none, he laughs. It's you he loves. It's you he thanks in his evening prayers. -Everville
It could be as simple as drivers if your audio is freezing. Weirdly, (it was with mine), it might be your graphics drivers. Check your audio and graphics drivers are the most up to date before anything else.
"Driver IRQL not less or equal" has been an issue with some nVidia drivers; if you're using an nVidia card that would be the first thing I'd look at. But any driver could cause it - the error is telling you that a driver is trying to access something it can't.
The culprit is most likely the last driver you installed before the errors began.