DAC and ADC Simutaneous Testing

I have a DAC and ADC in a controller board. DAC generates a sine wave of 20mV pp ,2.5Khz to a DUT (Device under Test. And DUT after processing the signal generates an amplified version of input signal. The output signal is fed to an ADC which reads the samples of analog output(100 samples).But the problem is i cant function both DAC and ADC simultaneously. Want help in this regard