If you are using your Pix-Star to stream pictures from a Netgear ReadyNAS 1000S or 1100 models be careful to check that you run the latest software version in the ReadyNAS.
Versions below 4.10.1 seem to have some stability issues in the connection with the frame and also folders inside the NAS are not visible from the Pix-Star.
Upgrading to the 4.10.1 proved to work and have those issues disappearing immediately.