On Rosh Hashanah, the common practice (as far as I know) is to blow shofar before musaf and during musaf; before the first set, we say the bracha לשמוע קול שופר, and this bracha covers all the shofar blasts of the morning.
Meiri (Brachot 11b ד״ה והרי) discusses the brachot of מלכויות, זכרונות, and שופרות, and how they don't obstruct the fulfilment of the mitzvah of shofar (during musaf), and vice versa (cf. Rambam Hilchot Shofar 3:13). He adds that if someone had a shofar but didn't know the brachot of מלכויות, זכרונות, and שופרות, they should say the bracha לשמוע קול שופר (ie. the three brachot in musaf are like the ברכת המצוה on shofar, and without them, we need to say a specific bracha on shofar).
Question: What is the case here? Is this a case where the shofar blasts before musaf were not sounded, and so the first bracha of לשמוע קול שופר wasn't already said? Is this a case before the pre-musaf shofar blasts were even instituted? Did Langeudoc (where Meiri lived) not sound the shofar before musaf? Or perhaps Meiri requires saying the bracha twice, once before the first set and then again before the further blasts? This latter is hard for me to accept, since why would we need to say the same bracha again immediately after the first set?
