|Hello, Usually it the other way around the the phone affects the router and cause droped signals. If you are having in issue my recommendation would be to change the wirelesss channel on the router till it clears up.|
If this does not work try using a different cordless phone to see if the problem still present. Also if you do NOT have DSL Internet you don't need filters the filter can cause static in the line when they are not needed.
If also make sure the base of the phone is not near EMI (electric magnetic interfernce) such as a microwave or TV.
If all these attemps fail I would invest in a Cordless phone set up that is 6.0 direct. They do not interfer with Wireless router because they run at 6.0Ghz and more wireless router out now are either 2.4Ghz or 5.8Ghz
Post back with your results! Hope I covered all the troubleshooting steps to fix your problem.