phone apps with slow response time when using home WiFi but behave normally when using mobile data work around?

[graberweg]

Has anyone ever experienced a slow laggy response times (up to a minute) when trying to use random apps on your phone while connected to your home WiFi? I've had this annoyance while trying to use apps like Ring, Fedex, UPS, and Twitter. The odd thing about this though is when I disconnect from my home WiFi and switch to mobile data, these same apps now are responsive and connect immediately to the internet without delays. My download speed at home (which I've checked numerous times) is about 300 to 400 Mbps while on home WiFi. What would cause this and is there a work around? I'd hate to buy a new wireless router only to find out it fixes nothing. I have a Linksys WRT 1900 ACS connected to a Motorola MB8611 cable modem. I've been dealing with this annoyance for the past year or so as best I recall. I began noticing this as far back as when I had a Samsung Galaxy S7 and currently I'm using a Galaxy S20. I also know its not specific to my phone because even my laptop and home PC experience similar issues when connecting to the windows 10 version of the Ring app (long delays before connecting.