How incredibly frustrating.
I've had trouble on and off with Comcast throughout the years. The main, and most annoying problem that I experienced was the connection simply dropping. I know I am not alone in experiencing that issue, as there are hundreds if not thousands of similar stories to be found on the internet.
Up until 3 days ago, I was using a rented Motorola Surfboard SB5101. I've had the disconnect problem throughout the years, and the symptoms were always the same. I'd be browsing the internet, a page would hang or time out, and the network connection icon in the system tray would indicate a problem accessing the internet. I'd look down at the modem to find that it had dropped (all lights were no longer lit and it was trying to re-acquire a signal). Normally when this happened I would have to unplug the modem, wait for a few minutes, and plug it back in. This would *usually* fix the problem, but only temporarily. Once it lost signal, it never seemed to reacquire one again on its own (though it's very possible that it did that while I was at work or asleep and I just never witnessed it). What's odd was that the problem was sporadic, meaning that I went pretty much all winter without having to touch the modem but I noticed this spring that the problem came back big time. Like I said, I've had this issue in previous years and went through the circus of calling Comcast, going through their troubleshooting routine, etc. even though I knew my router and what not wasn't the issue. A few years back after I had gone through a particularly bad episode of this and called several times, they finally agreed to send a technician out. Of course, by the time they arrived 2-3 days later it was working again. They logged into the modem, said my signal levels were fine, and left without replacing anything or doing any in-depth troubleshooting. At some point I went to the local Comcast office and replaced the modem with another provided Motorola Surfboard 5101. Sadly this did not resolve my issue, but at least it eliminated my old modem as being the culprit.
I continued to have the drop-outs and just dealt with it, as I felt at that point that I would just have to deal with the issue (even though I was dissatisfied with paying for service that wasn't very reliable much of the time) and I had lost hope that calling Comcast would do any good.
So I would have days or weeks with decent service and other spans where I would be power cycling the modem to try and get it back online. As I said, last winter wasn't so bad but when the rain and warmer weather came this spring my connection became much more troublesome. I was losing connection several times a day (some of you losing your connection 2-3 times a day had it great compared to what I was going through). I didn't know if the temperature or humidity might be causing problems or if this was just coincidental that it seemed to act up more in the spring, because I can't say for sure that the same thing happened in previous years (it's all been a blur of spotty service).
Recently, after the problem resurfaced I started reading up on signal levels and found that I was right on the brink of what were acceptable upstream levels (I took from my research that this was one of the more important numbers to look at and that many people experiencing drops have too high of an upstream level). With the splitters I had been using, my upstream to the modem was right around 54.5 dBmV. Keep in mind that I had been able to use the splitters and have consistent internet for weeks at a time...I didn't think they were the only cause of the problem but I also realized that they probably didn't help so I removed them from the equation leaving only the modem on that run. Doing this reduced the upstream level to between 49-52 dBmV which seemed like acceptable numbers for maintaining a connection (with 52 still being higher than what I'd like), but even without the splittersthe connection was dropping out. I continued to research and contemplated ordering a singal booster with active return path...the Motorola BDA-K4-RA and Electroline EDA-FT08300 seemed to get rave reviews from cable/Comcast users so I kept those in mind as a possible solution. I didn't really want to spend any of my own money to try to resolve this issue since, in theory, I should be able to pay for the service and have a reliable connection without having to buy extra equipment (especially now that I had given up the desire to run signal-degrading splitters). With that being said, I was so frustrated that I definitely would have ordered a signal booster if it was the last option and was even thinking of paying Comcast to give me a dedicated run to the cable modem from the pole outside.
This past Tuesday was the straw in the camel's back, as I was unable to get the modem online for any reasonable period of time. I would do my usual power cycle routine and the modem might get back online for a few/couple of minutes before dropping again. I probably power cycled it 10 or 15 times that evening. Infuriating. Then, before I went to bed, it seemed that all hope was lost as I was unable to get the modem back online at all. Frustrated, I just left everything connected and called Comcast. Surpisingly, after explaining my troubles they didn't make me go through any troubleshooting this time and scheduled a tech to come out the next morning.
Of course, when he arrived the next morning my modem was online but I wasn't going to let him leave as quickly as the previous techs. I explained that this had been an ongoing issue, I told him what happened the last time I had a technician come out, and he agreed that it would frustrate anyone to have an unreliable internet connection that dropped so often. He checked the modem where the line comes in from outside and looked at the cables outside. After finding that he could reconfigure the runs to eliminate a splitter outside, thus boosting the signal to the cable modem, he did so and also replaced some of the splitters. He also reterminated some cable, tightened the connections down, and replaced my Motorola Surfboard 5101 with a Cisco DPC3008. I was somewhat skeptical of doing this all at once because I wanted to know exactly what was causing the issue (keep in mind it could have still been the tap near the pole or even an issue at the head end but my CompSci background means that I prefer to deduce by changing one thing at a time and analyzing the results of that change before making another...too many changes at once might fix the problem, but then you don't know what piece or component actually might have resolved it and what parts were just fine to begin with).
The technician activated the new modem and I was once again online. After eliminating an outside splitter, reterminating the connections and tightening them down my signal was now anywhere from 45-49 dBmV which was even more acceptable. He said that the previous 52-55 dBmV was within spec, but it was in the "yellow," meaning that I should have had a reliable connection as they typically start having major problems at around 58 dBmV and won't connect at all at 60 dBmV. He also ran a speed test and I noticed that while I don't remember how my download speed tested, my upload speed was a paltry 0.45 Mbps! I know speed tests can vary and some people consider them unreliable, but it shouldn't test that poorly on a geographically close server. Still, if this meant a stable connection I would have been happy. Of course, he didn't stick around long after activating the new modem and seeing that my signal levels were acceptable so I shook his hand, offered him a cold drink and told him if this resolved my issues that I would buy him a twelve pack of any cold beverage that he desired (of course I was joking, but I would have done that and more if it meant no more disconnects!). He declined all but the handshake and told me that if the issue persisted, I should call them back and they would at that point need to send a maintenance technician to check everything at the pole. He was satisfied with everything inside and directly outside of our home, and was sure that any lingering issues had to stem from somewhere beyond what he had already checked.
I had to go to work after he left, but I was pleased to see that my modem was online when I got home. However, it didn't take long for the exact problem being discussed in this thread to rear its ugly head. I noticed that every few minutes (seemed to vary anywhere from 10-30 minutes) my browser would hang, the page would fail to load, and I'd get the icon in the system tray that indicates there is a problem with internet access. Sure enough, I'd look at the modem and notice via the lights that it was cycling itself. The only GOOD thing about *this* problem was that normally I did not have to manually power cycle the modem, and internet access would be restored after a couple of minutes. Now...realize how frustrating this has been for you, and then consider that I actually deemed this an improvement over my previous situation!! It still wasn't acceptable, but it was a lot less of a pain to deal with believe it or not. I think I only had to manually power cycle the DPC3008 one time during three days; the other times it would re-establish the connection by itself.
Given that I now had a new problem (I was pretty sure that the signal levels were OK but the modem was cycling itself and, unlike the Surfboard, was failing to re-establish a connection) I began another research session and that's when I found this most helpful thread. It was by all accounts an issue with the DPC3008 (or its firmware), and despite power cycling it manually mine never did reflash to the Aug 2011 firmware build. I was on the verge of ordering the Ubee DDM3513 or the Zoom 5341J mentioned in this thread, but I decided to make a trip to the local Comcast office again to see if they had any modems besides the DPC3008 (I kinda wanted my old Surfboard back to see if it would stop losing connection now that my signal levels had improved, but realized that was probably unlikely). I stopped by on my way home today and they had only one modem besides the DPC3008 - a Scientific Atlanta DPC2100R2 that looked like it had been returned for whatever reason. It wasn't the Ubee or Zoom or Arris that I was hoping for, but it WAS something besides the DPC3008.
I took it home, got it reprovisioned and I'm happy to say that (knock on wood...) as of this moment everything is stable and I haven't experienced a single drop! Now, I've only been home for a few hours but this is a breath of fresh air and I'll take what I can get. I certainly hope things stay this stable, but right now things are looking good. My upsteam level is currently 45.9 dBmV - the best it's ever been - and my speed tests today have resulted in 20 Mbps down / 4 Mbps up (MUCH better than with the DPC3008). The internet is snappy, fast, and most importantly, I haven't lost my connection.
If the problems return, I'll be back at it again. I'll probably call Comcast and have them send a tech out to check the line at the pole level, or see if they can send me another modem (depending on the symptoms). Now the questions running through my mind are, if I hadn't bothered with having a tech dispatched to check things out, could I have solved my problem by putting a signal booster in front of the Motorola Surfboard? Maybe. If the previous tech had done what he did to improve my signal levels and without giving me the cursed DPC3008, would that have resolved my issues? Perhaps. But I guess none of that really matters, as right now things are stable and I'm not out of pocket any $$$. I may even still purchase the Ubee or the Zoom that I mentioned earlier, as people seem to be having great results with those, but for now as long as this Scientific Atlanta modem holds my connection and remains fast I'll stick with it.
I am truly sorry for the novel I'm written here, but it was almost like a release to finally document the issues I've had and hopefully see them come to an end. If any of you made it this far, thank you for reading and just know that I experienced the same issues with the DPC3008 that many of you have/are (plus another totally different set of issues prior to that). My first suggestion would be to check your signal levels and make sure everything looks good. If they do and you are still experiencing dropped connections - particularly if you are using a DPC3008, RUN DON'T WALK and try another modem as there seems to be a large amount of evidence pointing to the fact that this modem does have issues, at least with Comcast, at least with certain firmware. I'm not sure why some people aren't having issues with the DPC3008, or why Comcast is deploying these when so many people ARE having issues, or why they won't acknowledge the problem over the phone (surely they should be able to tell if it's cycling itself; even if they are showing a constant connection to the modem from their end they should be able to view the modem logs that would indicate it cycling itself every few minutes). But I digress. Good luck to everyone and I'll post back (with a much shorter post) if my situation changes or my issues persist.
~
