I'm intrigued by the nature of the BQM in the middle of the day.
If this were a case of congestion, we'd see lots of packets queued, and some packets dropped. Surely, therefore, we'd see both the red "packet dropped" portions *and* periods where the yellow (maximum latency) section were raised considerably. If 5% of packets were being dropped, surely some percentage would get delayed noticeably. Even 1% would show - one packet delayed out of the 95 that got through - yet there is no shift in the yellow.
Personally, I'd also expect to see the blue (average) rise too.
This is what "congestion" looks like on my line:
BQM. Busy hour isn't very noticeable here, but you can see *something* in the yellow and blue before you ever see the red.
However, with the yellow and blue portions sticking resolutely near the minimum, it suggests that the packet loss is not being caused by congestion. Or at least "normal" congestion with queues involved.
The most obvious, non-congestion, cause of packet loss is interference on the copper portion of the line. However, I'd expect DLM to see that rate of errors and intervene.
Here is a
BQM with packet loss from my first FTTC line, with the switch as DLM intervened.
I think I would probably unlock the modem, and start tracking the error counters, to try to rule this part of the network out.