Are you controlling the Jaguars via CAN or PWM?
Can you describe the behavior of their LEDs when you reverse the control signal? (I
assume this is what you mean when you say "reverse voltage" - if you're actually reversing the polarity of the Jaguars' power supplies, well...)
Please explain what you mean by "disconnect" - do you lose communication with them temporarily, do they stop responding to changes in input, etc?
If you have a large load on these 8 Jagaurs, Wiifi is most likely correct in saying that by suddenly reversing the control signal, you're forcing a current fault condition (Jaguar firmware is written to temporarily cut control when current exceeds 40A; if this is what is happening, the status LEDs will slowly flash red and yellow for ~3s). The easiest way to rectify this problem is to enable automatic current ramping (see p11-12
here).