@LG86 I spent a solid week at it and in the end returned the set. I got zero indication of what the problem was (or could be). Good luck to you!

For the record I did try swapping the Decos, with identical results. (So I really don't think it's an individual Deco hardware problem.) Also it's clear at this point that my thread is misnamed - the...

Thanks for the response. I'll try to address your questions briefly and do more testing. 1. ISP is Comcast/XFinity. Longtime solid connection here, should be a non-issue. (My router is using...

This is a new (2-day old) installation of two Deco M9 Plus, in AP mode behind a home router. Both Decos are updated to 1.2.8 Build 20190403 Rel. 43515, and I'm using the iOS app version 1.8.6. The...