Differential Measurement Of My UUT

Hi,
I having problem using PCI-6025E for differential measurement on my UUT (an audio product, BTL output).
I had switch to differential mode in MAX. Measurement connection positive (ACH0), negative (ACH8).
I able to get the RMS value and freq of the measurement however the waveform is not uniform (unable to get beautiful sinewave).
When I use Scope to measure the UUT output, I able to get uniform sinewave.
I also tried to replaced the DAQ board however in vain.
May I know what can be wrong in my measurement?
Thank you in advance.........
Best Regards,
Norman

You might get better answeres in the Multifunction DAQ forum . The feedback forum is for site issues. Good luck!
LabVIEW Champion . Do more with less code and in less time .

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