I'm afraid 9 minutes of stats from an idle connection doesn't help much.

What I can see however is that in this case your router has synced at a lower speed so your noise margin is in a better range.

As I said before, I suspect at least part of your problem is that you were running the router at too low a noise margin i.e. it dropped to below 6db and this gave connection problems. If you've read the sticky as I suggested then you now know how to fix this? With your attenuation, a sync of ~3250kbps should be what you aim for. That will give you a sufficient noise margin to handle the normal daily cycle.