Coaxial Cable/Splitters Causing Problem for Modem?

Hello, I'm having issues with what I believe must have something to do with either my ISP (I have Comcast), or the Coax Cables in my house. I have a Motorala Surfboard Extreme, but I'm damn near 100% positive that it's not the modem that's causing the issue, as I encountered the same problem with a previous modem. Every night at precisely 11:45 the modem will restart (which I'm assuming is something that Comcast is doing, and not the modem itself). That's no big deal, I can live with it - except that the modem gets stuck when going through its reboot cycle. It powers on, and then receives packets from the ISP, but can't send any. That's where it gets stuck, and in order to fix it I have to unplug the Coax cable in the middle of it rebooting, and plug it back in.

If it's a problem with something only my ISP can fix, then I have to pay them to come out to my house and fix it for me. Is there a chance it could be bad cables or something? Or, the cable runs to two splitters before it reaches my modem (and then there's a third one that runs to a different story of the house from the original line, but doesn't actually have anything plugged into it), could that be the problem? For some reason it makes more sense to me that the splitters could be causing a problem, since the modem is having trouble sending packets back. Maybe it's just sending data to a dead end or something? I didn't know how practical this theory was, so I wanted to get a second opinion. I don't know. In the end I suppose I should just have Comcast come out and see what they can see. But, for now, could I fix the problem by just replacing my Coaxial cables, or removing that unnecessary splitter? Thanks.
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More about coaxial cable splitters causing problem modem
  1. Just did a hard reset of my modem. It doesn't get stuck on send every time it resets. Just occasionally.
  2. When is a splitter not a splitter...? Not all splitters are the same. Some amplify the signal a bit since everytime you split the line, you lose some signal. I think the splitters I have adjust by 3db or something like that. Your cable company should be able to check your line and replace the splitters if needed, but of course they will have to send out a tech to do this. This is also assuming this is the problem and it's not the modem.
  3. I have comcast also.
    Have them come out and split the main line with their splitter. one side of the splitter is for data only the other is for TV and Phone if you have their phone service.
    Do not mix TV and Data (computers) on the same split.
  4. mark_k said:
    I have comcast also.
    Have them come out and split the main line with their splitter. one side of the splitter is for data only the other is for TV and Phone if you have their phone service.
    Do not mix TV and Data (computers) on the same split.


    I have tv's and modem on the same splitter. Like I said, each side of the splitter is set to change the signal strength by a certain amount. For example, the tv side might be +5db while the modem side might be +3db or something like that.
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