Subsonic not accessible outside home network

[mais]

Hi all,
I have been using subsonic for a few years now and it had been running flawlessly - happily streaming music from my windows 7 pc through my d-link DIR-655 router through ports 80/4040. I use it everyday and find it to be indispensable.
Something happened in the last week or so - I changed ISP provider, bought a new cable modem - I'm not sure if this is the reason - but now subsonic is said to be running on my computer but I can't access it when I'm away from my home network.
any help will be much appreciated!
thanks,
mais.

Problem Description: as above

Troubleshooting Steps: I have rebooted wireless router / computer / uninstalled and re-installed subsonic (it was running the current version before incident) / I have called my new ISP for different name servers and tried punched them into my computer adapter settings/ I have tried setting up different static IP address for my computer / I have added port forward exceptions on windows firewall for both tcp/udp ports 80 and 4040

Playback Application and version: no joy from both iSub or internet pointing to ***.subsonic.org or direct IP:4040

Subsonic Version: 4.8 (build 3434) – April 17, 2013

Server Version: jetty-6.1.x, java 1.6.0_22, Windows 7 (70.4 MB / 88.7 MB)

Hardware Platform: Windows 7 Home Premium 64bit with service pack 1

Java Memory Limit: 69MB

Problem Filename: all files

Output from ffmpeg -i: 'ffmpeg' is not recognized as an internal or external command, operable program or batch file (I must be doing something wrong here)

Last ten log file lines: [10/21/13 3:59:51 PM EDT] INFO DaoHelper Checking database schema.
[10/21/13 3:59:53 PM EDT] INFO DaoHelper Done checking database schema.
[10/21/13 3:59:54 PM EDT] INFO VersionService Resolved local Subsonic version to: 4.8
[10/21/13 3:59:54 PM EDT] INFO MediaScannerService Automatic media library scanning scheduled to run every 1 day(s), starting at Tue Oct 22 12:00:00 EDT 2013
[10/21/13 3:59:54 PM EDT] INFO PodcastService Automatic Podcast update scheduled to run every 24 hour(s), starting at Mon Oct 21 16:04:54 EDT 2013
[10/21/13 3:59:57 PM EDT] INFO NetworkService Successfully forwarding port 4040.
[10/21/13 4:00:22 PM EDT] INFO VersionService Resolved latest Subsonic final version to: 4.8
[10/21/13 4:00:22 PM EDT] INFO VersionService Resolved latest Subsonic beta version to: 4.7.beta3
[10/21/13 4:04:54 PM EDT] INFO PodcastService Starting scheduled Podcast refresh.
[10/21/13 4:04:54 PM EDT] INFO PodcastService Completed scheduled Podcast refresh.