Intermittent Internet Speed Problem (drops to .5 Mbps)!?

Hello,
Im stumped. Every other day my internet speed will drop so low it's barely useable (can't stream movies, only basic web browsing). During these episodes download speed varies from .3 to 1 Mbps according to the Google speed test. Weirdly the upload speed remain normal 3-5 Mbps. I have Comcast 25 Mpbs package and I live in center City Philly. I haven't noticed a time pattern and have tried resetting the modem to no effect. There is a lot of WiFi traffic as WiFi constantly switch frequencies but that always happens and the problem is intermittent.... Ideas/trouble shooting tips?


Thank You

I didn't find the right solution from the Internet.
References  [url]https://www.cnet.com/forums/discussions/intermittent-internet-speed-problem-drops-to-5-mbps/[/url]



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