DC analog output is always added with a periodic signal

[labview2005]

DAQ Board:PCI-6111E
Software:Measurement & Automation 2.0/Labview6i
System:Windows 98SE

When PC is powered on,the analog output 0/1 of the board is always immediately added with a stable
periodic signal(cycle=0.6us,Vpp=15.0mv).The waveform looks like a mixture of sine wave and triangular
wave.
When the output is set to -10.00V(DC),the Vpp of the stable periodic signal is about 5mv,
when the output is set to 00.00V(DC),the Vpp of the stable periodic signal is about 15mv,
when the output is set to 10.00V(DC),the Vpp of the stable periodic signal is about 35mv.

What is the reason?

Any remedy?

The board is OK?

[George M.]

Hi,

The first that I would do is to update to the latest driver. This may seem like a simple remedy, but with such an older version of it, many things have been corrected. This will also help narrow down the problem. The newest version you will be able to use with LabVIEW 6.0 is NI-DAQ 7.1. Once you update the driver, verify that you are seeing this same behavior in MAX through a Test Panel. Please let me know if you have any questions. Have a Great Day!

George