Walks to the right in GPS or stabling after service

I sent my IRIS in for service because of GPS problems. That is why they are sending out the new foam tape for pixhawk. Now it I still notice that it walks to the right in GPS or stabling mode. Any advice? Also it seems that the gains are up on the movement. It was allot more stable before.

ok so I opened the IRIS and I have the new mods done from 3DR when it was in service and the new mods can in the mail yesterday.

But I still have a cal. problem. it walks to the right. I will try to open up the IRIS again to make sure that the PixHawk is in the right location from the factory.

You might want to tune your Loiter gains. See http://copter.ardupilot.com/wiki/loiter-mode/#Tuning
It might also be beneficial if you perform an AutoTune: http://copter.ardupilot.com/wiki/autotune/.
Hope this helps you out!