No sound out put through RC

[midhuncm2007]

I have an onkyo TXNR646 and LG smart TV ,both are ARC enabled.The set top box is connected to the TV via HDMI 1 and the TV is connected to the onkyo receiver via HDMI ARC.But can not hear any sounds through the home theater speaker,except we changed it to the TV speakers.In optical connection all are working well.Any body can explain a solution for this please.

 

[Ralston18]

Have you tried another known working HDMI ARC cable?

The following link may help:

https/www.lifewire.com/audio-return-channel-1846845