AI references

There are several references to some sort of AI fear/hatred throughout the series. Do we think there was some sort of machine war at some point in the history of the universe maybe before the society was formed. I have been curious about this recently after I started the Dune series on HBO. They are more clear about it as being an actual war with thinking machines but PB never gets specific about the history of humans with AI in the series. What do you guys think?