Constantly dropping internet connection

I'm about to be done with this and wash my hands completely if I don't get resolution very soon.

Been a customer for 5.5 years. Always had trouble with getting my service to be as advertised. Never been able to make advertised speed on internet until last week. I have gone through 4 modems in 5 years. I had my original surfboard DOCSIS 2.0 that ran flawless but never made speed. Always had a connection even if it wasn't very fast. Then I got a Motorola DOCSIS 3.0 modem that also ran flawless. Always had a reliable connection but never made speed. Then I moved because Apparently COX was unable to address the problem in my neighborhood with line quality, even though my signals have always been near perfect there was some ingress from somewhere outside the home that could never be isolated.....

Moving forward a year after my move still having speed issues plus TV issues. Technician comes to my home (again) and says "oh btw you do realize your phone service is running through this CISCO DPQ3212 you could run internet much faster from this device" So I let them hook it up. No increase in speed. still stuck at 26Mbps even though I pay for 50. Last week my internet starting dropping completely. I logged into my router all good there. I logged into the CISCO main page to see if I could check logs.....Oh no logs in that interface but I can see the interface so I'm talking to the modem....so the modem must not be talking to COX.

Power cycled the modem and walah internet works. 10 minutes later it drops. I played this game for an hour then called support. Lady said she could not see my modem. Funny I CAN!!!!...she sends a reboot signal and it reboots. internet comes back she hangs up. 18 minutes later internet drops in the middle of a steam download....I called back. next lady says "oh the device was un-provisioned" she re-provisions the device and reboots. internet works....for a half hour. 4 more hours are spent talking to people who obviously do not even begin to understand the hardware they are trying to support. I removed all possible causes by plugging the modem directly to my PC. reboot modem internet comes back up. speed test. 26Mbps (at least it's consistent lol) internet ran for about 13 minutes same scenario I could hit the modems interface but nothing past it. so Back to support and hours of uneducated guesses. I mean seriously these people are really taking stabs at this point. I even had one lady tell me I HAD to reboot my computer to make this work. Another guy told me that I need to reset my router... not just power cycle it but actually reset it. WHY? it works fine. Finally a T2 gentleman named Kevin pointed out I had tons of T3 timeouts. (how is he pulling this log. I want to see it.) He suggests my modem is faulty. COX cannot get anyone to my house in the next 48 hours. ARE YOU SERIOUS! 6 hours on the phone and you cannot get someone out here now ? why do I pay a car payment every month if I can't get support........

No Problem drove myself to the solutions store nearby and made the swap for another modem. Plugged it in and had internet in less than 5 minutes AWESOME RIGHT?....no. the internet died within 10 minutes. Plugged my PC straight into the device and internet held for a long time. so long that when Kevin called me back I was still good to go.... I ran a speed test and hit 48Mbps WHOA! advertised speed almost. Modem must have been **. cool seems like problem is solved. Left it like that overnight. Woke up on thanksgiving and guess what. Internet down. PC to Modem connection. nothing in the middle internet down. Screw it maybe it's a fluke I rebooted and it ran several hours just fine. I wanted to plug my LAN back in so I could get Internet back to all my devices. not just one PC. but obviously my router might be an issue as well so I waited until the next day to try it. I bought a new router on Friday. went from a tried and true Linksys WRT54G V1 with DD-WRT on it that has been working fine for 5 years to a brand spanking new NETGEAR WNDR4500 (n900) basic configuration and guess what. STILL LOSING MY INTERNET! through all of this I can still see the modem's web interface page at 192.168.100.1 and it says I have amazing signal.

I don't get it. for almost a week solid my internet has been dropping on the COX side of the line and NOBODY has an answer for me. Not to mention I work a REAL JOB you know one of those $65 an hour Monday through Friday gigs from 6am to 4pm. but there never appears to be any way to get a tech to my house when I am home. (mind you I waited three weeks for a senior tech to come out this Saturday... but the call center person botched that up and dispatched me a contractor who had no idea why the *** he was even coming out........so what else is there for me to try any ideas ?

I'll let this thread run a weeks course and see if I get lucky. If not. I'm going to move on with my life and make the needed adjustments. (which include litigation and reimbursement for 5 years of piss poor service.)