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#21
What I would Suggest in this situation is that you try, as a test, changing your DNS servers from those of your ISP to an independent.
The reason for this is that ISP DNS servers are often less than reliable
Open DNS is a good one to try https://www.opendns.com/start/
enter the following information manually into your router
Primary DNS
208.67.222.222
and if applicable
Secondary DNS
208.67.220.220
In your PC set your fixed IP address and also set the DNS address to your router address or it can be set to the above Open DNS servers.
Due to your location this may be less than Ideal as the majority of DNS servers available are US and Europe based although they do have locations in Australia.
If this gives you a more stable connection I would then investigate any freely available DNS servers more local to you.