Looks like that unit is 7-8 years old. As such, it is not a issue that is likely to be repairable, nor is it an issue that any money should be dumped into.
All in one, home theater in a box kits, are certifiable eWaste product. They aren't upgradable, when a part fails, the entire unit becomes trash. The speakers may be reused with a standard AV receiver, but not the subwoofer. So, a proper AV receiver would typically be needed along with a stand alone Blu-ray Disc player and a subwoofer.
The main unit and the 'subwoofer' module are more or less trash.