Sound Bar CT800 HDMI Arc has no sound when switching from other sources/input

[Sony_AU]

Hi Sony community,

I purchased Sound bar CT800 and had issue with Audio output from TV after using bluetooth or HDMI ports on the soundbar itself. Somehow the soundbar become confused about the signal. It cannot switch back when I want to watch TV.

I manage to solve it and thought to share it here.

Setup

--------

TV: KD-55X8500D

Sound Bar: CT800

HDMI Cable from TV (HDMI ARC Port/HDMI4) to Soundbar (ARC Port)

Both TV and Soundbar are on the latest software update

The Soundbar works fine on TV until I start using different sources i.e. Bluetooth or connecting my laptop directly to one of the HDMI port on the soundbar. Upon switching back to watching TV, it lost communication.

The symptom started with error message: Audio System Communication Error. 

I followed the troubleshooting in https://community.sony.co.uk/t5/android-tv/hdmi-arc-issues-ht-ct390-amp-kd-43x8307c/m-p/2190596#M150...

I even did hard power cycle (unplugging tv, all hdmi cables and soundbar) from power points, factory reset and try different HDMI cables. but still not working.

After few hours of troubleshooting, I manage to resolve it.

What I did was simply to plug hdmi cable from TV (non ARC port) i.e. HDMI 3/ to Sound Bar's HDMI ARC port. As soon as I did  this, I can see on TV displaying message "Audio Systems Active". Then I just have to swap back the HDMI ARC cable from TV back to Sound Bar HDMI Arc Port. 

This is somehow does the trick to "wake" CT800 soundbar again/establish connection back on TV HDMI ARC - Sound bar HDMI ARC port.. I can replicate the issue by using BT/Spotify then switch to watch TV. CT900 will not produce any sound.

Similarly when I connect laptop to the soundbar's hdmi port. As soon as I switched back to TV, it becomes confused and CT800 is no longer recognise the signal from TV.

Should I be concern? Is this product faulty or just need software update to address bug/defect? 

Any comment is appreciated.

[cass_n]

Hi @Sony_AU - I'm just checking this with one of our product experts and will update this thread when I have a response.

Cheers,

C

[cass_n]

Hi there - I have checked this for you and it sounds like there could be an issue with the Soundbar, so I recommend that you get in touch with the dealer you purchased it from (or you can contact Support to help investigate further - details here).

[Sony_AU]

Thanks for the feedback. The problem went away already for quite sometimes and now it came back but I think I know exactly what happened. If the soundbar is connected on HDMI/ARC port both from TV and soundbar and if the power is switched off from the wall rather than using remote control/the unit itself. This will cause audio system communication error. 

Even after powering back on, the system will think the audio communication is still active until I plugged hdmi cable (non arc) from tv to the soundbar hdmi/arc port to trigger/wake the sound bar.