Why is the DAQ outputs distorted?

I am trying to output two voltage sine waves(90 degrees out of phase) from my DAQ card. I use a for loop to create two arrays of 1000 samples each. I then send each of these arrays to my DAQ card for sampling of 5000S/s. One of the outputs(measured on an oscilliscope is perfect while the other clips and is distorted. Why am i not getting twp perfectly good sign waves?Is this a hardware issue?
Please find attached my LabView file.
Thanks,
Gilly
Attachments:
Sine_forloop_nearlydone.vi ‏91 KB

I haven't looked at your vi yet, don't have 8.6 on this machine (please identify the version when attaching vi's), but do have some questions. Are they both set to the same amplitude? Are you looking at them individually (re: single channel scope) or both channels at the same time? Are they both connected to the DAQ inputs in the same way. Usually, if there isn't an actual hardware problem with the outputs, distortion and clipping are caused by; 1) trying to output a waveform of an amplitude greater than allowed, 2) trying to drive a seriously mismatched load. In the later category hooking up to the DAQ incorrectly might cause a problem.
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