Am with Owen on this. I suspect it's nothing but random phase in the records, be they commercial recordings or advertisments, that are artificially being placed somewhere in the listening area.
When the announcer is in front and the music fills the back half of the listening space, it's deliberate - especially when many shows and advertisers use the same format.
But why? Why would they bother? The number of listeners who would actually decode must be vanishingly small. The ROI for the mix would be poor.
Was just musing this posting and that of KFBKFB where the posts make little to no sense, as if attempting to genrate posts.
Maybe they put the music through some sort of spatialiser to spread it wider in the L/R speakers to create more separation from the announcer? And the way that works happens to mean DPLII decodes the music into the rears? Whatever it is, it's intended for stereo or earbud listening since that is how nearly everyone listens. With probably a nod to mono listening due to people using a smart speaker. Surround decoding will be the last thing on their minds.
