SCXI-1125 module is providing bad readings when sampled after Open SCXI-1125 channels

[TA]

We have a 5 Volt Reference on the last channel of 1125 module.  If the previous channels are open, there appears to be an intermittant frequency/oscillation appearing on the reference signal.  If the open channels are grounded or we remove than from the sampling, the bad sampling goes away.   All channels are configured for differential measurements.   It looks as if the previous channels are causing the sampling amp to go into some type of oscillation?  Can anyone recommend a way to fix this problem or have seen this before?  thanks

[Tom_W_[DE]]

Hi TA-

I have seen this behavior before, and the unpredictable results of sampling open channels are actually expected.  The modules are designed to sample only channels that are grounded or actively driven, and when they are left open there can be all sorts of problems with ghosting and channel saturation.  More information is available in this KB.

Is there a particular reason why you want to sample un-connected channels?