Why does my broadband connection appear intermittent or slow?

An intermittent broadband connection (possibly accompanied by a flashing light on your modem or router) may be caused by the broadband service automatically adjusting your speed in order to maintain the fastest possible stable connection. This process is known as 're-synching' and is usually triggered by electrical interference affecting your phone line. The re-synch process requires the broadband signal to be dropped for 20-60 seconds while a new stable speed is identified. Not only does this interupt your work if you are using the connection at the time, but it will also cause the line to slow down to try and compensate for these drops over a period of time. The best speeds are achieved by having a stable connection.

Here are the steps you can take yourself to diagnose and fix most broadband issues.

Intermittent connection?

Please check the following:

  1. Make sure that your modem or router is placed on a desk or table, not on the floor
  2. Keep all electrical devices at least five feet away from the router, especially:
    • Halogen desk lamps with dimmers
    • Any electrical dimmer switch
    • Stereo or PC speakers
    • Televisions, monitors, microwave ovens etc.
    • AC power cords running parallel to the telephone line
    • Electronic insect electrocution devices (bug zappers)
    • Low quality 900MHz cordless telephones
    • Any other emitter of high frequency electromagnetic radiation
  3. Replace the micro-filter

Radio interference

Rarely, faulty or poorly designed electrical equipment inside or close to your home can emit excessive radio interference that affects your broadband connection. To work out whether this affects you, consider:

Sources of interference

If you can identify the faulty equipment that's causing the interference, it may be possible to replace it or turn it off when you need to be online.

Faulty electrical equipment (usually due to a faulty or failing component within the power supply):

Faulty lighting equipment:

Slow Connection?

First, check the above, as slow speed is often cuased by an intermittent connection. If this does not improve matters follow these further steps:

First, run a speed test for comparison

  1. Visit http://speedtester.bt.com (We recommend you use Internet Explorer for this test)

  2. Follow the on screen prompts and enter the phone number of your ADSL line.

  3. When prompted enter your broadband username (Usually in the format dsl-1234-x@power.net.uk, you can find your DSL reference on your invoice)

  4. The test will now run and can take a few minutes to complete, once completed you should be presented with the following information:

The information we will be using for comparison is the Down-Stream DSL connection rate. (Once this figure has been stabalised at a certain value for a certain period of time the IP Profile, which determines the amount of throughput which can actually be achieved on the connection, will be adjusted by BT's equipment automatically to correspond).

Please don't run this test too often as it can adversely affect the results. Running the test too often can appear to various monitoring systems as very high line usage and has the possibility of accidentally falling foul of the fair usage policy which would be counter productive to finding any issues that may exist. We would recommend only running the test once every 3 hours if it is necessary to run it more than once.

Check for faulty microfilters and phone equipment
  1. Unplug all your broadband microfilters and phones except for your broadband router or modem and its associated microfilter. You should include all corded and cordless phones, fax machines, Sky set-top boxes, and any phone-connected burglar alarms.
  2. Restart your router (switch off, wait 30 seconds, then switch on),
  3. Run the test again, if the DSL connection rate increases, this indicates an issue being caused by one of the devices which has been removed.
  4. Reconnect your microfilters one-by-one, then reconnect your phone devices one-by-one, repeating between each a router power-cycle and the speed test described above. Again, if you connect a device which is causing interference, you should see the connection speed drop (you can then double-check this by disconnecting the faulty item and power-cycling the router before repeating the speed test. It should revert to its previous speed).
  5. We recommend you leave the faulty device permanently disconnected or arrange to replace it.
  6. If no faulty microfilter or phone equipment has been detected, proceed to check for faulty home internal phone wiring below.

Check for faulty home internal phone wiring

Poorly-installed home phone wiring or poor quality phone extension leads (often with a flat rather then round cable profile) are the most common causes of slow broadband speeds. This is because they are more prone to electrical interference, which causes Broadband data speeds to be reduced compensate. You can test for this as follows:

  1. If you have a phone master socket like the one in the photo here (that is, square with a horizontal groove halfway down it, and removable upper and lower cover), we recommend you remove the lower cover as shown, taking care not to dislodge any wiring. Do not remove the upper cover. This will reveal a test socket on the right-hand side. This connects directly to the exchange, bypassing your home phone wiring and extensions.

  2. Plug your router or modem directly into this test socket via a microfilter.
  3. Recheck your connection speed as per the speed test above. If your connection speed has increased significantly, this indicates a likely fault or interference source within your home wiring. If it remains unchanged, this indicates either no fault, or the fault or interference is more likely to be in BT's wiring or in your local exchange.
  4. If you do not have a master socket of the type shown above, or cannot plug your router or modem directly into it, we recommend you minimise the length of any phone wiring between your master phone socket and your router or modem, avoid the use of flat or aluminium phone extension leads (go for round copper cable instead, which may sometimes be marked 'DSLMax-compatible'), and route cables to avoid areas of electrical interference such as near power cables, digital phones, microwave ovens, Christmas tree lights, high-wattage equipment, halogen lighting and so on.

Connection speed vs throughput speed

The tests above measure connection speed – the maximum data speed your phone line can support. Fluctuations in it usually indicate possible wiring or interference issues, either in BT's network or your home phone wiring. However, the speed at which you see web pages or download files is determined by more than just the speed of your phone line – this is also governed by the speed of your computer, congestion in ours and BT's networks as well as in the Internet (Such as the speed of website servers etc.)

This end-to-end speed is measured by 'throughput' speed - the actual rather than maximum speed your data is travelling at in given moment. Throughput is the speed reported by most online speed-test websites. It is normal for your throughput speed to reduce significantly during the day, as this is the time when network and Internet congestion is at its heaviest. We impliment different levels of traffic prioritisation to counter this. (You may wish to talk to our sales team about being upgraded to a higher priority level if you feel your not achieving the speeds you expect from your connection). You can test this by carrying out a speedtest after, say, 9pm (in other words. during the off-peak hours) to compare the difference. (Note that a slow throughput speed is not generally an indicator of a line fault).

Important note about speed tests

Every time you switch off or reconnect your router or modem, your broadband service refreshes your connection speed. Note, however, that where this has increased, your throughput speed will not increase for a further 3 days. This is a to minimise the risk of data loss which would occur if the exchange tried to send data down your phone line at a faster rate than it is capable of handling.

To avoid this happening, your exchange waits for three days of consistently higher connection speeds before it will increase the speed at which it passes data down your line. Also note that if your connection speed dips for any reason during the three-day period (eg. due to electrical interference or a fault), the exchange will restart the three-day period.

For these reasons we recommend you leave your router switched on all the time, and avoid measuring your throughput speed until three days after you last switched on or rebooted your router or modem.

Connection still not improved after 3 days?

If, having followed the above steps, you still believe you have a line fault or interference issue, then please contact the technical helpdesk on 01908 242 103 or via email to support@powergroup.co.uk.

Tips for optimum broadband speed

Here are some recommendations to ensure you achieve and maintain the best possible speed performance from your Broadband service:

DslMaxInformation (last edited 2008-10-10 11:30:08 by michael)