• Launch Winamp
• Click "Options" and "Preferences"
• Under "Plug-ins" locate the DSP/Effect section and click it once.
• Look for "Nullsoft SHOUTcast Source DSP...."
• Click it. A new window will open
• Click the "Input" tab and set the drop-down to "Soundcard Input"
• On "Input settings" - select 44100khz, Stereo
• Winamp will send sound to the computer's default soundcard - we need to now set that up to grab sound from the computer.....
• Click on "Open Mixer" - two mixer controls will open - we are concerned with the one marked 'Record Control' - set the fader on Stereo Mix to approx 50% and ensure the Select tab underneath this fader is ticked.
• OK now back to Winamp.....
• Click the "Encoder" tab and do the following...
  1) Click Encoder 1 in the left list
  2) Select "MP3 Encoder" for the Encoder Type
  3) For "Encoder Settings", Choose 24kbps
• Click the "Output" tab and do the following...
  1) Click Output 1 in the left list
  2) Click the "Connect at Startup" box
  3) Under Output Configuration, you will utlimately need to place your Shoutcast server address details - 
  e.g.
     Address = rs1.radioserver.co.uk (the server details supplied by M2M)
      Port = 8000 (the port number supplied by M2M)
      Password = (the password supplied by M2M) 
      Encoder = 1
  4) Click the box "Automatic Reconnection..." and set the time to 30 seconds.
  5) Find and click the "Yellowpages" button
  6) Untick the box "Make this server public" 
  7) Make sure "Enable Title Updates" is checked and "Auto" is selected for the two options below.

Once you have completed the above info, your Winamp should attempt to connect to SHOUTcast. If you see errors here, double-check all the fields in the DSP for typos. Most common reasons for DSP errors are:

• Incorrectly typed password

• Incorrectly typed IP address 

• Incorrect port 

• No Description or Genre - if 'Make station public is ticked'

• Software-based firewalls are interfering (We'll cover that next)

(tutorial courtesy of IORSN)