I'm absolutely stumped and would really appreciate any sort of help to troubleshoot this.

I've got a Zotac ION mobo - has run Mythbuntu for some time, from probably 10.04 - up to 12.04.

It hasn't been without complications but generally this has been isolated to AV issues.

A couple of things have changed recently, the big on being upgrading to 12.10 (the other the ISP).

Since then all I've had are issues with local networking with ubuntu/mythbuntu. It's super super slow - between 200 and 500 KB across the LAN (SMB share)

The media PC is connected to my TP Link router via a wired GB connection - which I've not had issues with.

My PC connects via N wifi - which doesn't seem to have issues with any other connections eg. downloading over 1-2 MB/sec from the Internet.

The Zotac mobo is an Nvidia ION (IONITX-F-E) - the NIC is identified as MCP79, and seems to download quick from the Internet too (again, 1-2 MB/sec).

There are no errors in the logs and from other devices, I get the same painfully slow speeds too.

I thought it may be the OS so reinstalled 12.10 (64bit and 32bit) as well as trying 11.10, and now 12.04 32 bit, but this behaviour remains. I don't remember experiencing any issues previously with 12.04 before upgrading. It's bugging me!

Does anyone have any suggestions what to look at to try troubleshoot this issue?