I would also guess it is a CMT issue. FWIW while it makes sense to offer Dolby sound on music focused networks, most of them do not. This is the same mess with Palladia which has been discussed many times on this forum.
Just wait for the next CMA or ACM awards, they are usually faithfully produced in 5.1 and aired as such as long as your local ABC/CBS stations don't mess it all up.