Off taste from Sankey tap?

I purchased a new sankey tap for my kegerator and used it for the first time recently. I had only been tapping homebrew until now and it seems like there was a little metallic off taste with this commercial keg or possibly the new tap?

I didnt clean it or anything, just tapped it and started serving beer. SHould I have done something to the tap before using it?

(I dont think its the faucets or the lines since i didnt detect this off taste with any of my homebrew kegs).

Any thoughts on this? The keg is now dead, should i soak the tap in something berfore the next keg?

I had a sanke kegerator in college and for the first few kegs it was always foaming. After a few kegs the foaming eventually went down.

Then after I graduated and had some money, I bought a cleaning system with some BLC (Beer Line Cleaner) and after I ran that thru the lines and then rinsed, the beer tasted so much fresher and better. I felt like an idiot for using dirty lines for so many years. After that, I cleaned the lines after (almost) every keg.

Moral of the story...clean your beer lines.