After months of frustration with my home phone line, and repeated call-outs by Telstra techs, I finally got it resolved.
I had bad static noise on the line making it hard to hear conversations and causing slow ADSL2 internet speeds (Between 1 to 4Mbps).
(No NBN in my area till early 2020).
Tried isolation tests, new modem, ADSL filters, replacement wall sockets, work on the pit in the street, you name it... Nothing worked.
Finally got a smart Telstra tech that found the issue... A break in the insulated wire in the pit, causing arcing between the minute gap and the static!
Now my phone line is noise free and I'm getting 11 to 12Mbps on ADSL.
Another two things I learnt through all of this as well through experimentation;
1. You can get an extra 0.6Mbps speed or so, using a direct ethernet cable from your modem to your PC rather than using Wi-Fi. (Especially if your Wi-Fi modem is some distance in your house from your PC, or even using an extender that is closer).
2. A better modem can also give you a little more reliable speed.
(If you have the cheap Technicolor modem Telstra supply you... Do yourself a favour and chuck it out).
