How about turning down the sound, or disconnecting the surround sound all together?
If she's losing her sense of hearing she may have a lot of trouble identifying what she's hearing. Not knowing what's going on would make her feel defensive.
Hearing is very important to a dog, not being able to identify sounds may make her feel vulnerable.
There is also the possibility of senility.
the thing is, as our pets age, they need special considerations, and possibly sacrifices from us, to make their senior years as comfortable as possible. A small price to pay for all the years of unconditional love, right?