lumbers, I’ve noticed that you are getting errors in Zoom. In my experience with Zoom and my ultra-long lines here in Skye, Zoom cannot cope with any kind of data corruption errors. I’m not certain about this, so the following may be wrong. I think that Zoom does not itself correct errors by resending lost or corrupted packets. Again, not at all sure about this, but it’s the best explanation for the behaviour I’ve seen. Most other internet programs use some software called TCP which lives (only) in the communicating computers at the two ends of the whole path and corrects for errors by retransmitting packets, and so an application that uses TCP continues to work and makes even a bad link look apparently ok by covering up corruption. Web browsing and email use TCP so that given that this is the bulk of the average home user’s experience many users don’t even know that they have a bad line. I think that a link has to be error-free in order to use Zoom successfully, again, no proof of this. Some sorts of live streaming internet TV (not Netflix or Amazon, BBC or ITV or Youtube) used to (or maybe still do) similarly require an error-free line.
I was saying before that your downstream SNR figure is way too high, suspiciously so, and it would be good to recheck the numbers. Also I may have misunderstood the slightly odd terminology that they’re using. It was this line:
Noise Margin: 6.5 dB, Down: 29.6 dB
But whatever the downstream SNR figure turns out to be, I was saying that reducing it to the normal 6 dB would make the line much faster. While this is true, doing so would make it less reliable and that’s the last thing you need for Zoom. The rule is : high SNR figure: slow speed, high reliability; low SNR figure: high speed, bad reliability. If your SNR is too high, then it has probably been raised because the line was very unreliable and raising it (high enough) will fix the problem. There is a limit to how high you can raise it though and if it can’t good high enough then your line is stuffed and needs repair. But I’m suspicious about that number, 29.6 dB, because I’ve never seen a line like yours at more than 15 dB downstream SNRM.