I have a room with 5 holes where speakers used to be mounted in the walls.

Each hole is the same size........a rectangle about 9 inches wide and about
14 inches tall.

Now that the speakers have been removed, I am left with filling these 5
holes. Cutting out new pieces of drywall to fit these 5 openings is not
hard. I am wondering how to attach the drywall, since there are no studs
anywhere near the cut-out openings.

Any suggestions are very much appreciated. Thank you.

Smarty