Curious how you came to identify that this generator feels different than the other 5.
The reason I ask is that normally one just designates one generator for contact use. Either you have a very unique protocol or you have a very inquisitive mind.
If by chance you were wiring yourself up to more than one generator in contact mode, you may have fried something.
Electricity will take the shortest path to ground. The use of two or more generators in contact mode is not supported, nor advisable, as current can flow from multiple sources into one generator.
If this does not apply to you, then the next steps is we need more solid data to be able to troubleshoot.
The exact setup you are running on the generators, a picture of the generator's screen while operating (both the good and the questionable generator), etc.
Otherwise we are shooting in the dark.
If I had the generator in hand, I would just hook it up to an oscilloscope and verify output.
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