work on your technique and learn to blow the call, lots of differences in calls. Once you cut the reed you are committed. Are you calling with your diaphram and not just blowing? I never handled a RNT call but many calls you can adjust the reed front or back but I would try to learn the blow it the way it is first. I have a Paul Kingyon custom double mylar reed duck call. The reeds are guarenteed for live and Paul epoxies his reeds in place do you can't mess with them. I have had it and sed it for over 30 years and it is still going strong. All Pauls calls came with a tape of him blowing your call. If the reeds ever broke, Paul would change them out free of charge. However, Paul has passed so if I mess up my call, I am SOL.
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The more I get to know about people, the better I like dogs