In regard to Musters and presentations, I just returned from a trip to Italy. The tour guides used devices so everyone could hear the narration. Amazon sells a variety of them.
I have experienced alot of trouble hearing the outdoor lectures at all the Musters. If we can't do something like an amplifying device then a paper copy of the lecture should be provided. The speakers are wasting their time if no one can hear them. I find it very frustrating at every Muster I have attended..