General. How to Fix Movies that Are Really Quiet, then REALLY LOUD. There has been no official statement of the sort by HP, just a consumer blogpost claiming he was told that by a tech support agent.
Either way, VLC is just making use of what the sound DRIVER provides. Lastly, they would have to prove you actually boosted the volume beyond the 100% and THAT was the cause of the damage. Or you can go back to using Windows Media Player... Personally I'd rather argue the 3 points I just made than go back to WMP XD I deal with around 500+ HPs daily, I've never heard this or experienced this.