While we have not experienced it ourselves, many users have complained about the ASUS Eee Pad Transformer Prime having GPS signal issues. Apparently ASUS has released an update that fixes this. Several XDA forumers have reported significantly improved GPS performance on their TF201 Transformer Prime with some users saying that they are able to lock on up to 10 satellites indoors!
There’s no official word from ASUS on this, so let us know if you’ve been asked to update the firmware in your Transformer Prime recently. The updated GPS software and build versions are 6.9.13 and IML74K.US_epad-18.104.22.168-20120117 respectively. See if your TF201 carry the same build and version numbers and let us know.
Good luck and thanks!