Ethernet Gateway delay issue

[AterMentis]

Hi All,

I currently have a full home automation system running on pi with domoticz and use arduino based mysensor nodes as expansions.
Some of these go through USB communication but i also have several wired up as an ethernet gateway using a big W5100 ethernet shield.
I used the example sketch from the mysensors site and just added devices and all is working well except for one issue...

Sometimes when i switch a relay device from domoticz its instantaneous... but other times i get the following error messages:
2019-09-20 20:54:42.414 Status: User: Admin initiated a switch command (854/Heating Zone3/On)
2019-09-20 20:54:43.616 Error: MySensors: Repeating previous command (2/2)
2019-09-20 20:54:44.817 Error: MySensors: Command not received by Node !! (node_id: 0, child_id: 3)

If you wait a few seconds to a minute it will eventually send the command succesfully and all will work but this is quite an anoying delay that shouldn't be there in my opinion... I have been looking everywhere on forums and found input to other users about baudrate and how you should lower it from 115200 in the Myconfig.h file of the mysensors library and i have tried going to 9600 and 57600 but this did no change the situation for me...
If anybody has any idea what else i could be doing wrong please feel free to share. Or if i can find it somewhere on this forum already written and i looked over it... my sincere apologies and thanks for pointing me in the right direction!

Kind regards
Jasper