If it came out of a 52DB then the MSR has a separate SA3 amplifier, an unpowered subwoofer, two jewel Cube speakers, and a Bose Personal Music Center remote.
Well, ours is a 58DB, but what you describe sounds plausible. Think I remember seeing two "boxes" of some sort under the master berth, and we have two Jewel Cube speaker pairs mounted on the bulkhead on either side of the TV. There were approximately 374 remotes down there for various stuff (TV, Bose I think, Direct TV box, DVD player, etc etc etc.).
Nothing much working, of course... which is partly explaining why troubleshooting hasn't been all that easy. Don't know what to expect, from where... and tracing/identifying cables hasn't been completely possible yet (partly due my other fix-it priorities).
The TV that was in the MSR was a replacement for the original... and I've since replaced it (moved it to the bow stateroom) with the TV that came to us in the saloon. (Which was flawed when we got it, somehow it fixed itself over the winter of 2021-2022.) Stand-alone mode, for now; I think we've watched that approx twice over the last year, so not a high pri.
-Chris