Please tell me what's wrong with my DAQ card(NI USB6211)

[Eyad_Yang]

I am using an NI USB6211 DAQ card and I input sine signals from ports No.15 and No.16. The terminal configuration is configured as differential. The sine signal is generated by the signal generator. 

But the signal I received through the DAQ assistant is not a sine wave. I used 100Hz and 1kHz sine signals to test, but the waveform is shown in the following figure.

So what happened to my DAQ card? Is it a wiring problem? What should I do next...

[altenbach]

Your images are too blurry to even see the configuration.

Are you sure the signal from the generator is OK?

How are things terminated?