See this post for instructions on updating IQ2s to 1.6.
We’ve noticed issues going to 1.6, but if you have already updated to 1.6 and still have network issues, there is undoubtedly something in the network which is having a negative impact. The IQ2 should likely handle the situation in a better way if that is the case, but one of the issues with wifi is the enormous variety of consumer networking products. It is impossible to test all possible scenarios.
It’s difficult to say using wifi is good or bad, because I think we’re headed in that direction regardless.
However, if you wouldn’t mind, I would like to get some info over to Qolsys so they can test and attempt to replicate. Would you mind letting us know your router model, and whatever model of additional access point the IQ2 may be using?