CallSubDelayed was one of the things I tried when trying to fix the error. However, in my case it provided unwanted results.
The service is used to retrieve data and populate items in a scrollview. This is done in its own activity. Specifically, it is a "guide" activity that shows a list of TV shows that are on at the current hour. The error occurred if the user backed out of the guide and went back to the main activity while HTTP Utils was in the process of downloading guide data and making callbacks to the guide activity in order to update the list.
When I used CallSubDelayed, it did indeed get rid of the error, but it also caused the guide activity to start up again even though I had left it. If I left it again while it was still updating, it would then return to the guide activity again the next time an item finished downloading.
So for me (unless it is just a problem with how I coded it all to work), CallSubDelayed did not work how I wanted it to.