I just bought a TCL Roku 32S327 TV. Found the audio a little lacking, so I added a soundbar.
Connected soundbar to the TV; tried optical, HDMI, and 3.5mm audio cable. Found that when watching live TV (over the air, with antenna) the volume was loud and clear. With the same volume setting, when watching Netflix, Apple TV+, or the Roku TV "Live TV" channels, the volume was much lower. Had to turn up almost all the way, and then the sound was not clear.
It sounds like this is a known issue with these Roku TVs. If there is no fix I will be returning it to the store TOMORROW, as that is the last day for return.
In addiiton to trying all different outputs with the same result, also unplugged the TV for over an hour, did a picture/audio reset, tried with Audio / Digital output format to Stereo as well as Passthrough (instead of Auto). Also, on this particular model it appears that when you are using HDMI/ARC and you are in an app and go to the audio settings, you cannot change the Sound Mode or Volume Mode.
