It's good that a Mod has got involved, but too late for me I think.
I have signed up with another provider as well to test things out. Although the issue has not fully gone away, I have to say that the understanding, ease of access, responsiveness, proactive reporting ( I could go on) with the other provider has been absolutley top notch.
But at the end of the day, the issue is the HFC network and this has been acknowledged by NBN through the other provider as a known network problem. I have also been advised by the other provider that NBN are doing some maintenance next week. I don't think this is a congestion issues because the other provider manages volumes through fixed plans (not unlimited).
Good luck with it...I have found this all quite a major disctraction due to the reliance on a good quality connection.
I'm now lined up to another provider who is helping me through this. I still have my optus account going, but the line is now serviced by the other provider and all your kit is turned off.
I couldn't really wait any longer despite considerable effort with chat, phone calls and this post. I think there is enough commentary elsewhere on dealing through your chat and phone support services.
But what I have found for your info is that it has been acknowledged by NBN as a Network issue. (I have been bugging them a lot on messenger, but they pull the "I'm a wholesaler, call your ISP" line.).
Finally, an end to the story.
Well, NBN finally detected interference from a neighbouring premises.
This was found out by NBN last week and fixed on 28th March. I've now been almost 4 days without packet loss.
I thought I'd post back here even though I am now with Aussie who helped a lot convince NBN it was an HFC network issue. NBN tried many times to say they had fixed it. I posted many times on messenger to NBN to try and keep the pressure up.
So it finally came good. Lesson learned - don't give up!
This took 4 months to resolve depsite many times me being told it was a problem with my setup. Happy that it's fixed, but disappointed it took so long and so much effort and cost to fix.