Whenever I hold down a key on my keyboard, my Windows 7 laptop goes all wonky. Graphics freeze and don't update until I release the key, and any audio starts repeating the last sound that it was playing. I'd love to give more information about the problem, but I don't know where to start with this one. I'm happy to answer any more questions you may have. Thanks in advance.
I hope this is the solution: if you have any of the Windows Sound Enhancements, disable them. It worked for me. Any software that you're using might be the cause. For instance, my sound gets choppy if I set an equalization preset with the IDT PC Audio software that came with my Dell laptop.