There are a number of different manufacturers who make adapters to go from line to mic. Check the Beachtek website. Search for similar adapters on the internet.
A shotgun would be better then the on board mic – but you’ll still get audience noise.
Think about borrowing or renting equipment:
- You can record audio separately, positioned closer to the speaker, and mix it in post.
- A lav will work best either wired to a recorder (audio or video)
- A wireless lav even better.
