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When a tie across measures, MuseScore plays as repeated two sounds. It should be played as one sound. How can you make it as one sound? Does it depend on what the instrument used, meaning if you choose the right instrument, it will play as one sound?
Comments
Are you sure you are using a tie and not a slur? Select the first note and move it up and down - a tied note will move up and down with it, a slurred one won't. If you have already checked this then post the score for others to look at.