Samsung UE40ES7000U E-Manual page 676

N
A USB storage device cannot
record until it completes the
Device Performance
N
The file systems of the PVR
output (Personal Video Recorder)
and the Camera app are different.
Therefore, you cannot save both
output types on the same USB
device. To make a recording using
the PVR and the Camara app, you
have to save the recordings using
Test.