It's a long shot, but I thought I would try posting here.

For the last week, I have been having some packet loss problems on dota 2 (Valve game).

It kind of looks like this in the game:

Obviously this makes for a less than satisfactory gaming experience.

What is strange is that this packet loss seems to happen only between approximately 7:30pm to 9:15pm ish every night (NZ time).

As part of trying to figure out the problem, I have continuously pinged several servers. 103.10.125.146, 103.10.125.147 and 103.10.124.120 are what I believe to be Valve servers. The first two should be based in Sydney and the third in Singapore. 

The graph below shows that up until about 7:28pm ish everything is fine, but all hell breaks lose from that point onwards. The graph going to -1ms is basically a time out, I just made it this way so its easier to see which pings are timing out. You can see the SEA valve server and telstra dropping at very similar times, then becoming stable again for a couple of minutes and then timing out quite badly again.

For some reason, the Australian Valve server seems to be ok based on the image today, but usually gives a lot of packet loss at similar times.

Note that I found the addresses to dota servers to ping via resource monitor -> network and could potentially be pinging the wrong Australian Valve servers!

I am a little bit of a loss to explain this situation. All pings to other servers (inc. google and my own router) seems to be stable at all times. My ISP is Bigpipe and I have been with them for many years without much issues.

I would appreciate any insight, especially on any particular tree I should be shaking for answers.

Thanks!