My Q7 television seems to get confused about the sound signal it should send via ARC to my soundbar. When this happens, no sound comes from the soundbar. The "Receiver (HDMI)" display will appear when trying to increase or decrease volume with the remote control, but will not show the + or - symbols above and below it (they appear when it is functioning correctly). Choosing TV Speaker in this situation will provide the correct sound.
The problem occurs when more than one HDMI input is turned on; if only one is turned on, ARC behaves correctly. For some HDMI connected devices, like a set-top box (on my HDMI 1) or a blu-ray player (on my HDMI 2), this presents no issue. But for others, like ROKU or Portal TV (on my HDMI 3), which don't turn off, the only way to solve the issue is to unplug the device.
My soundbar is connected on HDMI port 4 (ARC). None of the devices are directly connected to the soundbar. When the Portal TV on HDMI 4 is powered up, sound is correctly sent to the soundbar. But unless it is unplugged after use, sound from HDMI 1 is not sent to the soundbar, and the "+ -" symbols above and below the Receiver box are not shown.
The television recognizes the soundbar, and offers it as an option on the Sound menu. It is identified in that menu as "Receiver HDMI".
Any help on resolving this issue, and getting proper behavior from both the Portal TV and the set-top box devices would be greatly appreciated.