I have playing a Blessing BTR 1580 for well over a year now and I really like the way it plays and have never had a problem until today. Had a big band reh. this morning and about 2/3 the way through reh. it just would not play, it felt like a valve had turned slightly. it was really stuffy and I couldn't get anything out. I stopped, made sure my valve guides were locked in correctly. Iwould play about 2-3 measures and it would do the same thing. this went on for about 6-7 minutes [1 1/2 tunes] and then every thing was right again. I'm going to get ahold of Blessing and order new guides and see if this clears every thing up. I have had a tab break off of a guide one time so I know this isn't the case and the guides don't seem worn [have had that on a couple of older Benges]. When I got home I gave the horn a complete cleaning [did so about 2 weeks ago] and snaked out the horn just to be sure there wasn't anything floating around in there. Anyone else have a similar problem that just went away? Not sure I can trust the horn with out finding something wrong [just the machine repairman in me].