We use a different ad ID for each piece of content in our game so that we can track which piece of content an ad was shown for (long story). I'd like to start pre-loading the ad before I know which piece of content the user has selected. The problem is that I get an exception if I don't set the AdUnitID before loading the ad. I haven't found a way to do this, and I wonder if you have?
There is no way. The AdUnitId is what determines what ads to supply. If you don't specify it