Serial Binding Item ON issues after upgrading from 1.11.0 to 1.12.0

I’m having issues with items using the Serial binding. It started after doing apt updates, but I’m not sure exactly when, but I do know my items still work on version 1.11.0.

I’m using RFlink (not the binding) to switch on and off some 433mhz plugs and listening for my doorbell.
I’m using a combination of rules and items with ON/OFF statements.

an example of a switch:
Switch RFoffice “KontorRF” (Smappee) { serial="/dev/ttyACM0@57600,ON(10;NewKaku;011d9428;1;ON;\n),OFF(10;NewKaku;011d9428;1;OFF;\n)" }

This is the item I use to sniff for data to parse in a rule:
String RFLinkRaw “RF [%s]” { serial="/dev/ttyACM0@57600" }

It seems like all 433mhz traffic is captured by RFLink and passed on correctly and the OFF commands to items also seem to be confirmed by RFlink via a ‘RFLinkRaw changed from 20;14;OK;
to 20;15;OK;’, but only rarely the ON command gets any feedback from RFLink.

This means that I can turn stuff off but not on. It doesn’t help sending it from a rule either.

Any ideas?
Best regards