I'm preparing a patch using [netsend -u -b], sending to 192.168.178.255 with my home devices. This was working quite well, but suddenly one of them stopped sending data to this address
Does the outlet of [netsend] indicate that it is connected still? Maybe it hasn't stopped sending, but messages are not forwarded anymore by the router (assuming that your computers are using wifi or ethernet cable to router and are not connected directly). Hard to tell without more info. You could try restart the computers and even the router. So you also have a [netreceive -u -b] in your patch?
yes, it's connected. All computers have been restarted several times, I just tried the router as well but with no changes.
The same type of netreceive is being used, everything was working for a couple of weeks until it suddenly changed (without changing the patch or the system settings).
BTW: Have you tested if it transmission works when connecting to the other computer's IP address instead of the broadcast address? If not, does it work when you connect to localhost?
For sending, It works with 255.255.255.255, and the direct IP, but not with 192.168.178.255.
For receiving, It works with 192.168.178.255, and the direct IP, but not with 255.255.255.255.
In my both other computers, all these methods work.
Also, do you receive your own messages when sending to broadcast address?
Yes it does, with both types of broadcast listed above.