Yeah, QoS all turned off. Best I've got all day is 73/11 up, compared with 77/17 with the Openreach modem immediately before I switched over. Could be coincidence, but tomorrow morning I'll run a couple of tests with the 2850 and then switch back to the Openreach and see what happens. If it goes back up to 77/17 it will be a damning indictment, I fear.

Yes, I can confirm that another speedtest this morning using the Draytek modem gave me 71.43/12.05. I then immediately switched back to the Openreach modem, and got 75.05/17.76. That's pretty consistent with what I was seeing all yesterday.

On a positive note, the connection was stable for the last 24 hours, I believe. I sincerely hope these figures are as a result of me having done something stupid, but I don't think so.

no, you done everything right, its just the draytek, so now , the only thing possible to try or, whether someone wants to try, is annex B,ive unlocked my bt openreach modem and its def running annex B, being that half of the connection is fibre its completley possible that were now isdn if anyone from draytek is reading this can you give us some information in regards to wether annex B firmware needs to be used or not, theres no info at all, aprt from other users switching over to annex B and getting better speeds, but i need more info thatn just people switching over and getting lucky so to speak.Oh, did you rty telnet and enter those adsl commands earlier in post?. Just go in windows program and features, turn features on or off, and select telnet, than open a command prompt, type telnet, then open 192.168.1.1(what ever your webpage gui is),username and password for the draytek, then just type in the commands, there supposed to make a bit of difference, if i had my draytek plugged in i would try, but i have no spair plug sockets and am also trying to get my line stable again after all the messing around with routers/modems.

boe323 wrote: Oh, did you rty telnet and enter those adsl commands earlier in post?

Yes.

boe323 wrote: there supposed to make a bit of difference,

I'm fairly sure it only makes a difference if you have QoS turned on. Or rather, with the 2820 I had previously, it only made a difference with QoS turned on.

boe323 wrote: Just go in windows program and features, turn features on or off, and select telnet, than open a command prompt, type telnet, then open 192.168.1.1(what ever your webpage gui is),username and password for the draytek, then just type in the commands

Don't worry, I'm an IT professional who's nearer 50 than 40, and I know how to use Telnet :lol:

It intrigues me that BT Internet customers can connect fine with revision 3.6.1 of the firmware, but Zen Internet customers can't. There must be some setting in the exchange or the cabinet that makes a difference. I'd be interested to hear from any Zen customers using this firmware, to see if their upload throughput is reduced by as much as mine is. This thread mentioned 10% to start with, but my upload is reduced by 30%.

I'm on the 40/10 FTTC with PlusNet, and with the 3.6.2_232201 Annex A firmware my 2850n performs about 20% lower upstream on typical throughput speed tests (e.g. mybroadbandspeed.net) than the Openreach modem does. Download speeds are only slightly lower with the 2850n vs. the Openreach modem.

With the standard 3.6.2_2111112 Annex B firmware, my 2850n upload throughput is only about 3 to 4% lower than the Openreach.

In all cases, VDSL sync speeds (actual data rate) are identical on the 17a VDSL profile.

FYI, I tried the Annex B firmware off the DrayTek international FTP site, and it didn't make any difference. Still limited to 12mbps up, rather than the 17.5mbps from the BT modem.
DrayTek UK support now have my VDSL debug log, and various screenshots, so hopefully they can work out what is going on.