Meters are playing ping-pong. Argh!

Question

I know I'm missing something very simple. I am trying to acquire voltages in parallel from 2 Agilent 34401, serial ports 3 and 4. I'm only triggering 1/sec, but the meters acquire back and forth, ping-pong style. I don't understand this. Both are getting the same trigger. I only need to do a simple A/B math function but can't since both voltages need to be read at the same time. This is driving me nuts. 
PaulG.
"I enjoy talking to you. Your mind appeals to me. It resembles my own mind except that you happen to be insane." -- George Orwell
Solved!
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Answer 1

Have you built a table of values that go to your meters?
Since you are reading a single point, your meters are showing that value.  If at each iteration the values are:
5
1
8
3
8
5
8
6
3
8
6
9
2
6
4
On a scale of 0 to 10, you will notice the needle going back & forth.
For the same scale (0 - 10), if some of your values are over 10:
5
12 > 2
8
3
9
11 > 1
8
9
12 > 2
8
11 > 1
9
10
11 > 1
10
12 > 2
9
11 > 1
and so on...  it will be an even more pronounced "ping pong"