Output signal distorted

I have a pretty large VI which outputs high frequency signals to control some hardware and then takes an input from that hardware for image rendering.  My problem is that whenever I activate the imaging portion of my VI, the output signals become slightly distorted.  For example, a 1Hz sawtooth output doesn't ramp up smoothly but becomes slightly staggered.  This also messes up the frequency of the signal.  Does LabVIEW have problems outputting signals properly when another portion of the VI has a lot of cpu intensive processing?
I am using the "Simulate Signal" block to create a 1 Hz sawtooth wave, 128 Hz triangle wave, and a 65,536 Hz square wave and outputting these signals through DAQAssist.

Hi Laura,
I went ahead and changed the 65,536 Hz square wave signal as the first input, but the three signals still do not output simultaneously.  Although the signals slightly change as I vary the Samples per Buffer and Cycles per Buffer, I can't seem to get a combination that is capable of outputting these two low frequency signals with my high frequency signal.  I would either get an error message about "DAC conversion attempted before data to be converted was available," or there would be no error message but the signal output didn't match the given specifications.  Attached is the vi with the modifications.  Presently, there is no error message with the given sampling information, however there is no square wave output at all, and the sawtooth waveform only shows a partial amount of the signal.  I had to make some slight modifications to the Waveform Buffer Generation vi in order to allow me to change phase, duty cycle, and offset of my square wave.  I don't think this would have any effect on the Cont Gen Voltage Wfm vi though.  Any ideas what's going on?
Thanks a bunch,
Anthony
Attachments:
Cont Gen Voltage Wfm-Int Clk multiple waveforms2.vi ‏121 KB
Waveform Buffer Generation.vi ‏79 KB

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