Hello guys, I'm having a slight issue with my E-string. Whenever I seem to play an open E, there is a slight low pitched metallic tone that can be heard. It doesn't come up through the amp (At least, I don't think it does, my amp is very poor) but when practising with the volume down, it makes enough noise to distract me. Is this an issue with the string or perhaps the bridge? And is it an issue that can easily be fixed? If not, I'll just have to whack up the volume to mask it. Cheers.