Video Output level and high frequency roll off

Hi

I am using the DM6446 chip and the video output level from the DAC of the VPBE is:

1. 0.950Vpp, when DSP application is not running; i.e., it is only running ARM9 processor.
2. 0.920Vpp, when DSP application is running.

Input signal used: Composite NTSC 75% color bar, 1.0Vpp video level.

Is there a reason for the difference in voltage levels (delta=0.030Vpp) between the two? Or is this normal?

Our customer noticed high frequency roll off in the video output waveforms, is there a low pass filter inside the DAC of the DM6446 chip itself? If so, what is the cutoff frequency?

Thanks