Unable to generate sine wave

Hello everyone!
I am currently working on my Bachelor project at a company. i am stuck with a problem.
I have designed a labview program for vibration test system. I have used cRIO 9076 as the controller with NI 9263(as D/A) and NI 9234(as A/D).
The loop works as follows. the input is given from the labview program. it is then sent to the cRIO. the output of CRIO(that is output from NI 9263) is given to the amplifier. the vibration shaker vibrates based on the input from aamplifier. then the accelerometer detects the vibration and sends it to the NI 9234 and loop repeats iteratively. since i have designed a sweep sine vibration system, the output of cRIO is a square wave. it should be sine wave.
the probelm is i am getting a square wave as output from my NI 9263 which should be a sine wave output. I have two subVI where i use nominal to binary convertor(for NI 9234) and binary to nominal (for NI 9263) as calibration mechanism.
the question is where have i went wrong? what should I do to get a sine wave?
PS: on searching NI i found out some formulas (to generate sine wave) and designed a FPGA and LabVIEW program to generate a simple sine wave and got a sine wave. if that formulas is to be included where should i include that?
Thanks in advance.
Regards,
Vishal.

Without seeing your current code, there is no way we can even uess as to why you are creating a square wave instead of a sine wave.

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Hello Benje,
The problem/difference you're seeing is indeed in the coding and also in the sound card.
In the "working" example you're using the Simulate Signal VI with the following settings:
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In the non working example you specify:
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Is there any reason why you used different functions to generate similar signals in the 2 VI's?
Kind Regards,
Thierry C - Applications Engineering Specialist Northern European Region - National Instruments
CLD, CTA
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