SOLVED - Samsung Soundbar S700D disconnects from Samsung Q80D TV

[Saxony Snow]

Update Jan 14/25

After months of troubleshooting a technician finally solved the issue of my Samsung soundbar disconnecting from my Samsung TV every time I turn it off and QSymphony via HDMI eARC is also working properly for the 1st time.  

The TV has 4 HDMI ports. I have my cable box plugged into HDMI 1, my Blu-ray player in HDMI 2 and the soundbar in HDMI 3 which is the only port that supports eARC.  However, for whatever reason, having the Blu-ray player in HMDI 2 was causing interference of some sort. Once I unplugged the Blu-ray player from the HDMI port, and did a power reset by unplugging the tv, soundbar and cable box, everything worked perfectly. I can now finally control the soundbar using the TV remote, QSymphony works and the soundbar automatically starts and connects when I turn on the TV. 

Since I hardly ever use the Blu-ray I'm ok with keeping it unplugged until I need it, knowing I'll have to unplug it after and reset everything. 

TV is Q80D 2024 model, soundbar is S700D 2024 model.  Every time I turn off the TV, it loses connection to the soundbar when I turn the TV back on.  The ONLY way to reconnect the soundbar is to unplug it, then when I turn it on it connects again. Samsung customer service have remotely performed every trouble-shooting solution they can think of over the past 2 months and even sent someone to replace the main board. Problem persists so now they're insisting it's an issue with the soundbar.  But I've purchased 4 soundbars so far and all have the same problem.  The first 2 soundbars were S60D - I bought the same model twice because customer service said the problem was the soundbar.  Then purchased two S700D soundbars with subwoofers, again same issue.  I've updated the firmware, factory reset the tv and soundbar multiple times, and used multiple HDMI cables.   Any suggestions? 

Update:

Samsung sent out another technician who replaced the main board and the wifi connector. Problem persists.  

Is there anyone out there with this model tv and this model soundbar? 

[Kev55]

My Soundbar does this every now and then also, make sure your HDMI is a high speed 2.1 cable if you haven't done so already, also make sure it's in the eARC HDMI port in the TV however I'm sure Samsung would have done that if they've been round.

[Saxony Snow]

Thank you for your reply. I just ordered 2 new different HMDI cables from Amazon that will be delivered on Thursday.  Hopefully it's as simple as that. However, is there a specific brand or specs other than 2.1 that you'd recommend?

These are the ones I purchased. 1 is $13, the other is $18. Not sure if there's any real difference. 

Micro HDMI to HDMI 2.1 8K@60Hz, Micro HDMI Supports Ethernet, 3D, HDR and eARC

And

8K 4K Micro HDMI to HDMI Micro HDMI 2.1 Adapter [8K@60Hz, 4K@120Hz] 6K, 5K, 48Gbps, HDR, Compatible for Samsung

[Kev55]

That sounds like you've got really high spec HDMI cables so I don't think you could do any better, hope you get it fixed

[Saxony Snow]

Great! Thanks so much, I'll let you know if they work. 

[Saxony Snow]

Thanks again for your suggestion. Unfortunately neither of the new HDMI cables made a difference, so Samsung is sending another technician out. 

[Saxony Snow]

Thought you might want to know that my issue has finally been resolved. I updated the post. Thanks again for your help.