I have a wedding that I filmed and all through the ceremony feedback was coming through the house speakers. What do I need to do to remove it or can I?
Let me rephrase that. Is there a method using the EQ or some other plugin that Vegas already has that will allow me to remove the feedback? Izotope is good but I can't justify the cost for this project.
You have to find which frequency is ringing. Sound Forge makes this very easy with it's spectrum analysis tool, but you can find it by trial and error. Create a notch filter in Graphic EQ. This is done by adding a control point to the frequency curve line at the feedback frequency and then two more control points as close as you can to either side. Drag the middle point down all the way. Frequencies at that notch will be removed.
Some adjustment will be required. Often you'll have to open the notch a little wider. Feedback also tends to have harmonics. If you find the main frequency is, say, 430Hz*, then you may also have to remove 860Hz, 1290Hz, 1720Hz, etc. though the amount of reduction required decreases quickly as you go up to higher harmonics.
* 430Hz is about what i got on your sample when i ran it through Spectrum Analysis. Try that frequency first.