I find the pics you've attached difficult to view, but I can't see anything obvious in them.
Are wired and 2.4GHz connections OK?
What devices are they?
Have you split the two Wi-Fi bands? I'm guessing you have as you're specifically mentioning 5GHz issues.
- Scan your Wi-Fi environment with a suitable app or inSSIDer to see if there are any interfering signals (less likely but still possible on 5GHz)
- Try changing the Wi-Fi channel
- Check the devices have all updates including Wi-Fi drivers
What sort of 'reset' have you performed - ensure you do a full factory reset.
It could be a bug with the router.
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I know a bit about Wi-Fi, Telecoms, and TV as I used to do it for a living but I'm not perfect so don't beat me up... If you make things you make mistakes!