There is a basic solution to this issue that no one has really talked about - some people have talked about cleaning, but no one has really said how to do it yet. This is what I have done in the past - and keep in mind that valves tend to be pretty tight during the break in process - is that several times during the first month or so, I'll take a valve brush, a cleaning rod, and a fair amount of good, clean cheese cloth, and I'll clean the valves out. First things first, scrub them out with the valve brush, but then swab them out with the cheese cloth and cleaning rod, and clean the valves off as well. You'll notice a fair amount of black that comes off and onto the cloth - that's probably buffing compound and other grime left from the manufacturing process. A former band director of mine showed me about doing that with new horns and it always helps during the break-in process, and it helps to eliminate that issue. I had it with my Kanstul flugel when I bought it too - after a few times doing that, I had no more issues.