Someone needs a network nerd? Well, you probably don't need to look any further.
As for honest hunches with my own experiences; if this stuff is failing only occasionally, and if you have an old router with the same SSID, that may be causing collisions and/or conflict. You can, using the same SSID and passkey on ALL routers, do a repeater network. If this is what you are attempting, this sounds like a misconfiguration.
And if this is Linux, even better.