Stern and George Gomez have announced a Service pack for Avengers to deal with a few issues some people are having with the launch ramp moving slightly, and the top ball gate not locking 100 percent of the time when it is supposed to.
These are very minor things, and most people (IF) they have had these issues are making adjustments n fixing the little things themselves, but the physical service pack is something they will be sending out to those people who dont want to fiddle without a factory answer/fix.

The last Stern model to have a service pack was Transformers, also a George Gomez title.  
Something tells me something got rushed towards the very end of both Transformers n now Avengers, and a few minor tweaks have been required on some machines only. Its not the end of the world, but one would think with computer technology these days, these things should have been caught before production (remember the captain america inserts also on the Pro). No huge biggie, it will get fixed like everything else, and Avengers is still a excellent title, but some early units have had a hassle. Perhaps current and future production models will have these issues produced out of them with factory fixes/service pack added before shipping.

If I hear anything on what the service pack includes, i will post straight away.