Hello. We have a facility with these pre-configured devices. One of them broke, and they replaced it with a standalone unit. They report that the speed was previously 900 Mbps, but now, with the new one, the speed is only 40 or 50 Mbps. Why could this be happening?

This is a recurring issue where the configuration gets erased, or a device gets damaged. Could you please send us instructions on how to recreate the factory pre-configuration?

Try to find and/or reconstruct the default config scripts in a wireless-wire pair
Like this one viewtopic.php?t=210892&hilit=cube#p1097127

In that same thread there is a link to this post on another thread:
viewtopic.php?t=205042#p1059476
Where the standard configurations of a pair ( both master and slave) are posted.
Since you already have one half of the old (good) configuration, It should be easy to recreate the other half with those bases.
From what you report (working but much slower speed) It could be possible that they are using the (backup) 5GHz connection instead of the primary 60GHz one.

In the end the problem was that I was transmitting at 5ghz instead of 60, once checked it was solved. Thanks for your help.