I'm using the $59 adsl2+ unlimited plan with a promised speed of 12 Mbps. However, the speed I am getting only maxes out at 2 Mbps, with 1.2 being the average and 0.02 being the slowest. I read somewhere that having multiple devices that use wifi can have an impact on the speed each device is getting, but I also heard of a problem where a client was promised faster speed but got a slower one because of a mistake from the ISP limiting it. I have around 14 devices in my house that uses internet with 5 that uses it all the time. I would like to know whether if the speed I am getting is normal or not.
We do not promise any ADSL speed guarantee since there are several factors that will determine the actual speed delivered. One major factor is the length of the copper cable from the exchange to your premises. You can check this by entering your address in the lower left box of the TPG Map (https://www.tpg.com.au/maps/). The table in that same page will also give you an idea of the sync speed other TPG customers' modems are getting. The quality of each copper line will also affect the speed so you will most possibly see a variation in speed even for those within 100m radius of your location. Compare your sync speed by checking the Status page of your modem's setup page.
Now, to determine the approximate speed you are getting from your internet service, do a speed test (speedtest.net) from a computer wired to the modem. Turn off the modem's wifi to ensure there are no other devices using the bandwidth that may reduce the test result.
Post here the results (cable length, modem statistics and speed test result) if you need further assistance with your speed issue.