Recently I switched from using WestNet's broadband on ADSL 1 to Optus's ADSL 2+ in the vain hope that I would squeeze a little more sync performance out of my connection. My Netcomm NB9W modem was syncing fairly reliably at 4.3MB on WestNet's 8MB service at a distance of about 4.3 kms. I practically cried when it dropped to 3.1MB when I switched over. How could this be I wondered? So I started looking around for answers...mainly on the Whirlpool Forums
1. Apparently Optus uses a brand of DSLAM that is made by Hua Wei and not the Ericsson/Alcatel units that others like WestNet (Telstra) and IInet use - these are'nt syncing as well with Broadcom based modems (hearsay).
2. They are planning firmware updates that will hopefully improve performance and stability.
3. I tried updating firmware on my modem and plugging into different wall sockets around my house.
So after getting really annoyed with the performance, I called their helpdesk number. After persisting with their irritating voice response system...I finally got through to a person. They tried a few options like putting me on a different profile - that didnt work and made it worse.
Eventually I talked to one guy who said to try bypassing any filters, unplugging all the phones and connect the modem directly into the wall. I got about a 400KB increase - hardly anything revolutionary but better. So I started to plug the phones back in - one at a time and the performance stayed good. So that got me thinking. It must be the ADSL bypass filter that was holding it back. I left the ADSL modem plugged directly into the wall via a standard phone double adaptor. I plugged the phone into the other side with its little ADSL filter....all good still.
Still not happy with the fact it was now only 3.5MB I pursued further.
The NB9W has a whole bunch of options to disable certain ADSL settings. So I switched off ADSL2+ and ADSL 2 and only left G.DMT running which effectively dropped it back to ADSL 1. Hey presto Im now getting 4MB!
At least Im close to what I got before now!
So heres all those in a summary:
Hope this helps!