I am pretty disappointed with this. Is this congestion?
Quite possibly. I would suggest pursuing the issue with Zen, as they are not a cheap supplier.
unless you happen to be connected to an exchange that has a zen LLU presence (pop) then this congestion will be down to BTW's network,(back haul) possibly a SVLAN or other part of bt's network
If you are seeing similar via the BTW speedtester /P tester and it's offering a TAP3 test then run that by changing your log in details and DNS servers set to auto if they aren't normally or it wont work, (BT assume quite wrongly that everyone uses their isp's dns servers), but don't run more speed tests on that tester until Zen support have seen/recorded the low performance results , as each new test will overwrite the previous result
Once you have the proof that zen require in order to raise it with BTW , they will likely ask you about availability for an engineer visit, though an engineer visit would be pointless, (because they can only check the copper pair to your home from the cab)
this is down again to btw systems, which is successful at wasting both the isp's &customers time, stalling IMO before they actually look into it, and if possible move you onto another Svlan that has a lower utilization level , BTW run their kit hot in parts of this country
Had peak time issues a couple of times , but they got resolved after a little hoop jumping , like testing connected direct to BT modem(no router) to see if it gave different results , but i suppose they like to rule out EU equipment regardless
Edited by tommy45 (Mon 28-Dec-15 00:57:10)