|When you say blue port is that the port you've been referring to as "mic" port?|
If so, you may be in luck as this is the 'Line In' port. There may be no physical damge in that case. You could try a complete removal and reinstall of your soundcard drivers (rebooting between removing the current and reisntalling). While you're in the process it'd be worth checking online for an updated driver if one's available.
If however, you had the amp connected to the pink port (the actual 'Mic In') then Richard59 is correct. There could be damage to your sound chip.
IT Services Manager