Not at all sure, to be honest, about this: "Audio cable connection from dish receiver box to sound bar".
Do you have the Owner's Manual?
Does the following link match your product?
http://www.lg.com/us/support-product/lg-SH2
Are you able to provide more detail about the devices, the cables, ports, and the connection paths that you are using?
For example:
Dish receiver ---signal ----> Sharp TV----> lg sound bar ------> sub-woofer/speakers.
With more detail per ports, cables, and connectors.