| Hi stoneroses, if I'm understanding you correctly, "warp" means that there is some curvature along the neck, right? So you were trying to straighten the neck by tightening the truss rod? After tightening the rod, when you sight down the neck from the headstock, is it "perfectly straight" or is there still some curvature?
Here's a couple of things you might want to consider.
First, fret filing is probably not the solution, and it should only be done as a last resort and when there's a specific need.
Second, string buzzing is "normal" with a perfectly straight neck, even if you adjust the action up high by tweaking the bridge saddles. What's not normal would be if it buzzes on the fourth fret and not at the sixth, or vice versa, or if it buzzes on the lower half of the fingerboard and not on the upper (or vice versa).
Third, string buzzing may not be a bad thing. String noises are an essential part of many of the recordings we all know and love. How are you listening to the buzzing, through an amp or just acoustically? Are you looking for a "perfectly clean" sound?
And finally, you said "live with the high action caused by the warp". You do realize, that every time you adjust the neck by tweaking the truss rod, you have to readjust the action and intonation at the bridge? The neck should be straight or "slightly" curved, and all the other action adjustments are done at the bridge (usually, although in some basses like Alembic's there is also some adjustment at the nut).
What kind of bass is it? What kind of bridge does it have?
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