I agree with "dean" on this one. As the customer, I wish it weren't so. But if I were to put myself in the manufacturer's position I would definitely void the warranty. If I built a product and warranted it to perform within certain parameters, then the customer modified my design and pushed it beyond the original performance envelope, I would decline any sort of responsibility.
It sucks, but look at it from both perspectives.
It sucks, but look at it from both perspectives.