Loss of Wi-Fi signal

I keep intermittently losing the 2.4 Ghz wi-fi signal, the 5 Ghz seems more reliable, but also not continuously available either.  A reboot seems to fix the problem, then a short period later and the signal is again lost.  I've tried setting it on a different channel from all other devices nearby with no help.  I've gone backward in firmware versions from the current V1.0.0.104_1.0.104 back two versions previous to V1.0.0.88_1.0.88 and the loss occurs less often but still occurs.  I could still back up 2 more versions to V1.0.0.70_1.0.70 but it doesn't seem at this point that would completely cure the problem.  Anyone have any ideas what my next step should be?  Or should I just make this router a boat anchor and by a new router?  Only had it a couple years, hate to waste the money!

Thanks!

Bob