If you have reset both the AVR and rebooted the modem/router to no avail, then time to call Yamaha for warranty repair. As the unit is only 1 month out of warranty, Yamaha may still honor it. If not, many credit cards will provide an extended warranty of 1-2 years as a free benefit of the card, so that may be an option as well if Yamaha doesn't come through.I have an RX-A860 that is having trouble connecting to my WI-fi network. It has had sporadic problems in the past with streaming Sirius via the MusicCast app, but I just chalked that up to a buggy app. Now, however, the problems have gotten worse. Yesterday after I was unable to stream Sirius through the app, I did a factory reset. Initially, the receiver used a really odd IP address via the default DHCP configuration. The IP address was not even in the range of my network. I manually assigned a static IP address within my network, and after several resets I was able to connect to the receiver via the MusicCast app and the Yamaha AV control app. I could also verify via my Unifi configuration that the IP of the receiver matched the data within Unifi.
This morning I am again unable to connect to the receiver via the MusicCast app or the Yamaha AV control app. However, I can still see the receiver in my Unifi control panel. The receiver IP within Unifi has not changed, and it shows a good connection. I also cannot reach the receiver directly via a web browser.
I am pretty sure I am doing everything correctly, since I also have an RX-A3060 with the same setup, and everything has always worked fine. That unit streams fine from the MusicCast app, is visible within the Yamaha AV control app, and can be accessed via a web browser.
Do these receivers have knows issues with Wi-fi? Is it possibly a network issue? Of course, the unit went out of warranty about a month ago!