Modifying load bearing studs
A header will need to added in that area. Perhaps for the short span, it needs a triple 2X4 on their edge will work for that, 2X6 would be best. This is assuming  2X6 wall. They can be directly above the speaker or even as high as the underside of the top plate if the angled blocking does not complicate anything. Some blocking will need to be added for the joint between the foam board and OSB.