Hanging up the phone interrupts wireless

Problem:

Hanging up our cordless phones briefly interrupts our wireless connection. Just long enough to be disconnected from online games.


We are using DECT 6.0 Vtech phones (definitely not 2.4 ghz phones)
We have verizon FIOS internet (not DSL)

I've tried changing channels in the modem with no success.

Any ideas? At this point I'm frustrated. Googling the issue just gets people telling me I've got 2.4 ghz phones, DSL, or that i should change the channel on the modem.

Are your router and the phone base on the same electrical circuit? If so, there might be RF interference being transmitted to the router power supply or the FIOS 'modem'. This can be eliminated by using a good quality power strip with an RF filter for the router and modem.

hmm. actually that didn't seem to solve the problem completely but the spike/disconnect doesn't seem as bad.

I disabled the wifi on my cable modem and I'm just using a linksys e2500 dual band router.

I separated the 5gz and 2.5 ghz connections, and i've tried both at this point on various channels, with the same results - if i'm playing a game I'll have great ping (30ms) and if i make a phone call, it is fine, but once i hang up the connection is briefly interrupted.