Hi! In case you aren't aware from your monitoring, there seems to be packet loss between SYD1 and SJC1.
I am seeing high packet loss from a Sydney tunnel for traffic to the United States:
2 e0-1.core2.syd1.he.net (2001:470:0:27b::1) 175.034 ms 181.569 ms 184.898 ms
3 e0-35.core2.sjc1.he.net (2001:470:0:51c::1) 325.544 ms * *
4 * * *
5 * * 100ge8-2.core1.lax1.he.net (2001:470:0:534::1) 331.783 ms
6 * hivelocity-ventures-corp.10gigabitethernet12-19.core1.lax1.he.net (2001:470:1:839::2) 331.858 ms *
7 fd80::afe:21 (fd80::afe:21) 378.718 ms * *
8 fd80::afe:e (fd80::afe:e) 387.989 ms 388.569 ms *
9 fd80::afe:79 (fd80::afe:79) 388.426 ms 386.764 ms 386.726 ms
10 fd80::afe:4 (fd80::afe:4) 395.726 ms 387.439 ms 387.03 ms
11 * * *
...
This started at around 2021-08-05T01:32:00Z and is still happening 10 hours later, so doesn't appear to just be some short term thing. I've run mtr a few times and am seeing the same pattern (packet loss starting on and after e0-35.core2.sjc1.he.net), so I think it is your international link.
I really love and appreciate your tunnelbroker.net service - if there is anything I can do to help you diagnose or test this, happy to help! :)
Please note that it is now working again.