Home Theater No Sound Troubleshoot -- 2

I need help with my home theater speaker system which comprises of 7 speakers with 4 mounted in the ceiling. Unfortunately, apart from 2 speakers next to the TV, the rest are not producing any sound. The problem appears to be with the Receiver/Amplifier and possibly the cables/connections.

Ideal Skills:
- Audio equipment troubleshooting
- Home theater system knowledge
- Cable and connection inspection and repair

Experience with similar projects is highly preferred. Please provide your proposed solution and estimated time frame for repairs in your bid. Thank you!