KNX binding sends commands with a big delay

I already had this problem with openHAB 1.x, as described in this thread:

Since switching to openHAB 2.1 at the beginning of November everything was fine with openHAB 2.1, the 2.2 snapshot and until today the 2.2 stable.

Today I noticed the same behavior as before:

  • When switching a KNX item through a rule the command is send to the KNX bus with a huge delay (several minutes) or not at all

  • When switching a item bound to KNX through the UI the state of the switch in theUIi changes and the event is logged to the events.log, but the lamp I used for testing is not switched on or off. The command is not received by the eibd daemon, running on a wiregate server, which I use as KNX interface (checked the eibd log).

What I tested:

  • CPU load of the openHAB java process is fine, RAM might be a little bit heigh (1.5 GB) compared to 880MB just after starting openHAB. But this should not be an issue

  • When switching the KNX group address on the wiregate command line using groupswrite everything works as expected, so I guess the eibd is fine.

  • Other bindings work as expected. Checked with the fritzbox binding, switching a DECT outlet. When switching the item in the UI, the outlet is switched in about a second.

  • Values are received from the KNX bus as expected, e.g. when switching a light at a wall mounted switch or receiving temperature values (checked the openHAB events log)

  • After a bundle:stop and bundle:start for the KNX binding everything works as expected again.

Especially the last test make me believe, that there is some sort of obscure problem with the KNX binding. Maybe someone else has observed this behavior or has any idea??

A merry Christmas to all of you!!