Cockroaches are not displayed. (House Flipper)

Long I searched for the answer, but almost nowhere in the Internet I found no such problems, the more its solution. And it is that where crawling roaches they are not. Or rather, technically, they're: there their sound, you can get a vacuum cleaner and even destroy their nests, but blindly, since they are not visible. I don't know how to fix it. Can someone faced with this?
PY.Sy.
Configuring, replacing them glass off. Even if you turn it on, then Windows will not be visible.