samba - Mar 2016 - Occasionally fails to do multiple simultaneous mounts

I have connected 8 identical devices to my samba server. The 8 devices are
connected to the same power supply and when I turn on the power all 8
devices will boot up an try to mount a share on my samba server
simultaneously. Most of the time this works fine.

However occasionally some of the mounts fails. Is there some limit to how
many mount attempts samba reliably can handle at the same time? Is there
something that I can configure to guarantee that all the devices are
allowed to connect to my samba share or is this a known issue?

I am running samba 4.1.23.

Best regards
Marcus