Isolated string-buzz

[Sonorous]

My fretless is buzzing in the area around the 9th-12th "frets".

This is the neck that came on my SX a long time ago, and I remember having the action really really low and having lots of mwah with no harsh buzz. Then I bought a fretted neck and put that on there for a while. The other day, I put this fretless neck back on there, and now it buzzes in the previously mentioned spot.

I've tweaked around with the relief and with the action, and nothing can cure it. It does get better with more relief, and does go away with super high action. I don't want super high action though, so I'm not satisfied with that remedy.

While being stored, I did have the truss rod loosened like it should be. When I eye ball the neck, it looks like it should, with no major warping... just the usual relief (based upon truss rod) in the usual position.

Any ideas on what to do? Should I try sanding the whole thing down a little bit? Where can I get a radius block?

[Sonorous]

Bump.

[mamm7215]

My 2 cents worth include a) Truss rod loose/rattling and b) Nut too low. A good tech would probably help as well.

[Sonorous]

I fiddled with the nut and that wasn't it either.

Could it be a rattling truss rod? I was trying to pinpoint the source to make sure it was coming from the fret, and I discovered that it sounded like it was coming from wherever my ear was held. I held my ear at my fretting finger and it sound like it was coming from there, held it near the bridge and heard it there, and then held my ear near the headstock and sounded like it was there too. Maybe thats just normal because its all connected to each other?

I placed a shim on the headstock side of the neck pocket to tilt the neck up some with actually bowing it. It helped a bit, but I still can't get the action as low as I wanted.

I'm going to try sanding it a bit, but I need to find a block to do it with to keep the radius.