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1; What is in the LOG when the Google Home disconnects? What is in the wireless->registration when the Google Home is connected.
You may need to add the wireless logging (http://forum.mikrotik.com/t/wifi-limitations/146079/1 )
- all depends on your config. Please share your configuration. In terminal, copy the output from command “/export hide-sensitive” or add here the *.rsc file made with “/export hide-sensitive file=anyfilename”