Lost the cruise control and had the engine revving up between gears last week. Googled the symptoms: broken clutch switch (P/N 8EO 927 189B). Took the bastard appart and fixed the contact spring with an iron solder. Et voila cruise control back!
Don't know how this temporarily fix will last but now I know I should order a new switch soon.

2007 A4 B7 Quattro manual

 

When My clutch switch went out with the same symptoms, it cost $ 84.19 at the dealer to fix.

 

I know this is a cheap repair; the switch cost less than 30 bucks. I was just curious to see what was inside to confirm the problem. It turns out that I was able to solder the half broken contact spring. Also the way it is designed is a recipe for failure; no wonder it is a common problem.