On a Michael Dolling, hex pernambuco, German, quite a fine bow, I have recently noticed a tendency to "skip" at a point around 1/6th from tip. Unless I've got a fairly high bow-speed/bow pressure stroke going, the bow partially loses a steady grip for an brief instant, always at the same spot. (don't know how else to describe it, I think you'll all know what I mean). In my experience on an older, cheaper bow I had same problem at different spot; I'm sure it was in the stick then because no changes of hair or rosin had any impact. Recently in my practicing I'm working extra hard on bowing, including forcing myself to learn to do be able to complete almost all strokes and attacks near the tip if need be, and to use the entire bow more uniformly. Never noticed this skipping problem before, so I don't know if it has recently developed, or if I just never noticed it cause I had the habit of relying too much on lower 2/3 of the bow. This bow has white hair about 1 yr old. During more than half than half of this time this bow was not played. I am using the fairly hard grade of Kolstein, forgot what the grade is called. Suspect I could minimise this problem by switching to stickier rosin, but for now am trying to improve the sensitivity of my right hand by working with a powdery rosin, applied sparingly. anyway, I don't think my current problem is hair/rosin. But if in fact it is the stick, I'm wondering what can be done, if anything. Any thoughts from any of you more experienced/knowledgeable than I ?