Ahhh I can help with the headphone jack! Gigabyte won't be able to fix that as it is a design issue and the interference you hear is the headphone jack being so close to the hard drive. This cannot be fixed but you can use this for your headphones as a work around. As for the speaker issue, no idea. Mine seem fine although I usually have my laptop sound playing through TV. I have none of them games! Could use Heaven Benchmark 4.0 (free) on ultra settings to do a synthetic test?