[BillSPrestonEsq]

sounds like he does not like the sound of his guitar in position 4. Turning the treble up might help, turning the mids and lows down might as well.

Other possibilities include
Bad Pot, probably guitar tone
Bad wiring
Bad tube
personal preference
need eq adjustment

I just switched rooms in my house I was playing in. The one that will be the nursery, there could not be enough treble, ever. In the room I am now in, turn that treble down and use a neck pickup to keep the same tone in that room.

[Dark Helmet]

^^^ he's also got the mids up and bass down.. likely need to pull the mids down too for the frequencies he's mentioning.