Do not connect the TV to the receiver for audio. Do not use the analog red and white cables.
Do use an optical cable from the player to the receiver. Note which input you used on the receiver. Then select that input on the receiver selector. That's how it Knows where to get the sound.
Do you know how to do the digital input assignments on the Yamaha? That is how you associate an optical input on the back of the AVR with the name of some activity on the receiver input selector, a name such as DVD.