3 WiFi adapter, WiFi constantly breaks together

This is the third generation of Devolo, which is in my application. The most trouble was the "blue" dLAN 85-generation, just always worked, no dropouts. Even something bitchy was the dLAN 200 generation, where every now and then adapter from the system, "disappeared" and had to be re-registered.

We currently use 7 dLAN 500 adapters, which 3 WiFi 500. The idea of ​​the WiFi synchronization seemed ideal in order to easily access every floor the same thing can Fi. Has also worked well at first, adapters were synchronized. However, I soon fell on that in the Devolo Cockpit software the adapter have repeatedly lost their names (there are all specifically named, so I can see if something is wrong, for example, is the name of the router just "router"., A Another is called "WiFi UG", etc.) So these names keep disappearing, the machine will no longer have, you can reassign the name. So you could just live.

The problem is that the WiFi adapter crash constantly, at all three crashes constantly from the WLAN. In the basement there is roughly every 20 minutes off, sometimes comes after a few minutes. again, usually you have to the adapter and plug it again. On the ground it will last longer, but also crash so here about 5-6 times a day. On the first floor every few minutes.

I then "decoupled", ie. each adapter has its own spec. Fi. Does not help, just rush from often.
I will now try to assign each a fixed channel. Does not help that, go back.

Two of the three are from a WiFi network kit, one was purchased separately, all a few weeks ago here at Amazon.

A word on the Service by Devolo: of the 200 series, which was a total of reliable, after about 4 months, an adapter was faulty. This was a birthday present (in the kit) was, I had the (randomly also Amazon-) original bill, but just issued to my brother, who had worried the set. The Devolo Service wanted me initially made to believe that ensuring only 'first' applies, and offered me to "return unrepaired for a fee or for free to dispose of" the appliance. Only on my answer, if I should send them the corresponding §§ from the law of obligations, so that they can assess the legal situation better, then came without comment a replacement unit. Not just a recommendation.