I was playing my bass last night using a headstock clip on tuner. I made sure I was in tune and started playing. I noticed when playing a C at the thris fret of the A string it didn't sound right in tune. In between songs I checked the open tuning and they were still on. The notes at the 5th fret were also in tune. However notes played on the 3rd and 4th frets were a bit sharp. Has anyone ever noticed something like this before? Could it be a neck issue? Being out of tune is one of my pet peeves.