Cisco DPC3825 slow, re-boot =OK?

[drkailey]

Upgraded to 80GB Express, changed to the Hitron CDE-30364 modem but had big problems port forwarding so switched to the older DPC3825.

Got it all configured but every couple of days the speed slows to a crawl (10 Mbps up), I re-boot the modem by pulling the power and it's back to 30+.  Went away for a week and it was down to 0.57 Mbps up!  

It's on the desktop hardwired to it, wireless connections are the same.  I'm using it as a "gateway", ie: modem and router in one. I see others bridging it and using router for wireless but that's not my issue.

I've replaced the unit twice and spent hours with tech support, they ping it and find nothing.  They wanted to send tech support but I doubt they'll find anything, I've triple checked all the connectors, cables etc. and all is good.

Any ideas?

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[ejyrejryj]

My reply might be somewhat unrelated, but having this exact issue with Shaw. As expected, support has no clue why. I confirmed it was with the modem because even a direct connection through the modem causes it. I've found similar cases online and it's always something on the ISPs end. For me, it started happening out of nowhere over the past few months. Maybe someone else who's having the same issue will find this useful.