Factory reset as in load stock firmware? I am using Asus Merlin firmware.ATT may have changed something on their side. Factory reset and manually configure to test .
Router has been on Merlin for quite a while now; over a year. Updated to latest version about a month ago - Current Version : 3006.102.5. Buffering just started a few days ago. I had it setup thru ATT router using IP Passthrough. I turned it off and reverted back to ATT router; just reconnected the Asus router this evening using a different SSID; so far so good - no buffering.Hi,
Others might be better placed to help, but perhaps you could provide the Merlin FW version, try to post (with personal info redacted) debug logs and confirm you did a hard reset after moving between stock and Merlin i.e. after the Merlin install you did a hard reset and entered everything by hand?
Merlin still reccommends a hard reset moving between Stock and Merlin FW and that it is usually not necessary from Merlin to Merlin unless specifically stated in the release.

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