I have two electric fretlesses - an old Tokai currently strung with TI flats with a 1.5mm E string at 12 fret action. Very smooth and nice. This has markers in a rosewood fingerboard. The other is a Squier VM as a backup, which has an ebanol board with markers. With the VM to start with the markers were slightly proud, which was easily solved with a sanding beam and some sandpaper stuck to it, straight neck, and I did some work on smoothing it out, with the truss rod slackened off. I've spent a fair bit of time working on it over the past couple of years. The action is currently set to around 1.7mm with .100 to .40 Dunlops for a brighter sound than the other bass. There are still a couple of positions where there is excessive buzz, e.g. 5th position on the A, unless I am very careful about the position. E.g. if my finger is dead on position there is no excessive buzz, but a couple of mm off (as happens sometimes) and slightly behind the position it buzzes. Mwah is generally good, with a couple of minor spots up the neck where there is a little too much relative to close positions. Any recommendations, or is it a case of just sanding a bit more (I generally don't take much off during any sanding episode)? There is no obvious dip in the fingerboard in that area.