Are there any rules of thumb / priorities how to place a module in product and route cables to obtain good EMC performance?

• Mount the module on a metal chassis, and screw it up tight
• Short mains cable and very short Earth cable to chassis, if Earth terminal on the AC inlet is used
• Speaker cables should not be routed close to the primary side
• A mains cable should not be routed close to the secondary side
• Twist speaker cables, and keep them as short as possible
• Keep audio cables short and use shielded cables if necessary
• Cables should be kept away from transformers and inductors