Please kindly check your TVs audio settings and audio interfaces first before setting up the connection to the soundbar.
-For audio cable connection, please make sure to plug the audio cable into a connector on your TV labeled Line OUT or Audio OUT, not Line IN or Audio IN. Please kindly note that the audio cable is connected to the TV audio output and the soundbar audio input. And you can double-click the AUX boost button on the remote control to restore the volume.
-For optical connection, please set your TV audio output to "Optical" and set the digital audio format to "PCM" (PCM is a digital recording of analog audio, and is an optional audio format in many televisions), and make sure the protective caps at the ends of the optical cable are removed before plugging it in.
-If your TV or other source devices only has a 3.5mm headphone socket, use the 3.5mm to RCA audio cable to connect the soundbar to your TV or other source devices.
-Sound bars for TV does not support Dolby Sound and DTS, please kindly disable Dolby and DTS on your TV, Netflix, Amazon Prime Video, HBO, Hulu, Youtube, and other streaming video apps.