We scored 3 against LA, the first two of which came while using a back 5.
I hope never to see 3 CB formation. 4-2-3-1 has worked much better for us. With 5 defenders we just look inept in midfield, barely creating any scoring chances.
I think the issue is more the 4-man midfield with 1 forward. I prefer a two forward set with a back 5 - it allows for a little more positional fluidity. And that is not a setup that this team is built for at all.