I just installed a 65" frame TV. All my external devices such as Xbox one and Comcast Cable Box are connected to the TV's Connect Box. I then connected the Connect Box to my Yamaha surround sound receiver via an optical cable. The issue is, when playing a movie from the Xbox or Cable Box, I don't get dialog from the center channel. I do hear sound from all other speakers. I do get full sound if I play a movie from Netflix via the Smart TV interface. I have changed the audio output on the TV to optical Dolby Digital. Any ideas what the issue could be?