cable internet speed fluctuating

I have had cable internet from Time Warner for about 3 years. In the last several months the connection has become increasingly slow to the point of uselessness.

I have noticed that the connnection slows down a lot when the weather is very hot and humid...also is slower during peak times of 8am to 11pm.

I have gone through several steps trying to improve it. The first thing I tried was getting a new modem. That actually made the connection slower. Then I had them put a new line in from my backyard to my house. That made it even slower still! I couldn't even get the modem sync'd for several hours. The next day I got another new modem at the tech's advice... :? That didn't help so then I got an RCA 2-way amplifier and a Monstercable power-pass splitter to boost the signal. That helped a lot. The connection was then at about 50% speed of the 4meg/sec that I'm paying for.

Today the tech's are coming out again to my house. We'll see what happens next. So far the tech's have been no help. The only thing that has been helpful so far was the equipment I purchased myself. Any suggestions on other things I might try?
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  1. i would suggest returning any routers that you payed extra for, if possible, and trying to find out what the speed that the cable tech is getting from his test equipment. do you have cable TV? getting any problems with that?

    I think that the cable company usually takes responsibility for the connection up to your house, but I could be wrong. have you considered the fact that you're trying these tests during "peak times"? cable is a shared bandwidth for your entire neighborhood and the only way to get an accurate test of the reliability of the line is to have 1 computer of your own hooked up directly to the cable modem (try multiple and see if it makes a difference) and run a speedtest physically close to your location, such as and choose the city closest to you and see how the speed is then (reducing the amount of slowdown from your own network at home).
  2. The problem happens with or without the router. I have taken my laptop and cable modem with a very long extension cord and hooked them up directly to the pedestal in the back yard thereby eliminating completely any of the problem being in my wiring to or in my house. The results were the same though.

    The tech that came out yesterday told me he would have a lineman install a new line from the street to my pedestal and possibly a new pedestal and see if that would help but otherwise couldn't understand why the poor connection either. He said there was minimal packet loss (around 1%) and that the decibels looked in the right range on his equipment but he got the same result with the slow download speed at the pedestal that I did. Onward the saga goes.

    He was a nice tech though and gave me his work cell number to call him directly if the new line to my backyard didn't help out matters when they install that tomorrow.
  3. This is a tough problem to solve indeed. If it gets worse when there is increased heat and humidity, I wonder if it could be some sort of grounding issue? Did you ask the technician if other people in your area are experiencing this problem?
  4. the tech said no one else in the neighborhood was having these issues. So, if it is a grounding problem could i check that by testing the download speed with the ground wire temporarily removed?
  5. I don't think removing the ground wire would be a good idea... but, check this page out:

    Also, you could try something like the "cable modem isolator" on this page:

    Sorry I can't be of more help. Can you get them to switch you to a different line on their end?

    When you replaced your modem, did you try a new brand of modem completely? I know that some modems are more sensitive to wiring issues than others, so you could try to find a more "hearty" modem and do some testing with it.
  6. Ok here we go. If its a rca modem try to go to or and look for a signal page, this is the webflash thats built into the modem to show you the signals that the modem is receiving this will tell you all. I think its in the signal or cable itself. A amp is not the way to go if you have bad signal or NOISE issues it will just boost crap signals which will not help at all. The other thing is make sure the line to the modem is dedicated and is not split via a splitter ( tech's love using splitters cause there lazy). Any splitter used after the main split coming into the house will weaken the signal more to the modem. If and when you get to the modems webflash page post a pic of the signals or write down the readings.

    Downstream signal._____db's
    Upstream signal.______db's
    Upstream power level._____dbmV's
  7. I am having the same issue. Any help would be great.

    I went to

    Software Version: ST31.08.01
    Software Model: A801
    Bootloader: 2.1.4c

    Cable Signal Details

    Forward Path: Return Path:
    Signal Acquired at 687.000 MHz
    SNR: 35.0 dB
    Received Signal Strength: 3.9 dBmV
    Micro-Reflections: 34 dBc
    Modulation: 256 QAM

    Forward Path: Return Path:
    Connection: Acquired
    Frequency: 23.0 MHz
    Power Level: 33.0 dBmV
    Channel ID: 3
    Modulation: 16 QAM

    Data Service Details

    Provisioned Address: Yes
    Provisioned Time: Yes
    Provisioned Configuration: Yes
    Registered: Yes
    BPI: Enabled
  8. imyoursuperhero the three reading that are most important are as follows.

    1. SNR: 35.0 dB This is a good reading (signal to noise ratio) Higher the better. The highest I have ever seen is 38 dB. Your good there.

    2. Received Signal Strength: 3.9 dBmV This good to it can be between -10 to +10 so your ok here to 0 is perfect.

    3. Power Level: 33.0 dBmV This is really good your right in the middle. The return power level can make a modem cycle alot and not stay online if it reach's 60 and above, a modem can run fine at 50 to 55. Yours being 33 is perfect. The power level is how far the modem is powering up to send its signal back to the ISP (return). Since your SNR is 35dB the modem is basically is not working hard to talk back to your ISP.

    From the readings I see your internet should be stable. what kind of problems are you having, modem drops off all the time, you move the modem and it goes off, only during a certain time of night, pings are high? What model of RCA modem to you have? It should be on the bottom of the modem it will start with DCM...?
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