Wn3000RP V1H2 - inconsistent connections

Firmware: v1.0.2.64-1.1.86. Modem/router combo: Sagemon F@ST1704N. Worked fine for several years. In December, existing devices (Lenovo yoga 2 laptop; MacBook; Lenovo thinkpads, iPhones) all started encountering issues. Finally pulled it out and put it on a shelf. Tried it again recently. Results are that the Lenovo Yoga 2 can connect, but everything else starts having problems or becomes unable to connec to either the netgear extended or the Sagemon router.

Is it just time to trash it and get a new one? We were pretty stable (no new devices) until this started failing in December.