I have a problem and I don't know what it is caused by. When I fret the b string on my guitar at the 7th fret it is muted by the next fret i don't know if it's fret wear or the nut or the bridge the nut is in good condition so is the bridge and the frets look good the truss rod I adjusted it was way off but fine now the action was high but I fixed that too it's just a beater guitar I got for real cheap so.