NVG108 Gateway Nuvo KNX problem when connecting to knx bus

[Davidoffke84]

I have (for several years already) a Tokka NVG108 KNX gateway for my NUVO audio system.
Since there has been way too much going on the last few years it was still boxed when I decided to install it a week or 2 ago.

When connected to the KNX bus there is a very strange behaviour.

• Instantly all device on the same ‘line’ lose communication with the bus. The bus stays ‘alive’, but there is no more communication possible.
  • F.e. when I put is as device 9 in the line that connects all my actuators there is no more communication on that line (line 1.1.xx)
  • F.e. when I put it as a device in the line with all my switches, detectors (line 1.2.xxx) there is no more communication on that line.

All switches stay ‘alive’ and there is no indication of a max current > Imax on neither of the power supply’s.
I’m 100 % sure all my connections are right, if I place whatever else sensor/motion detector or actuator on exact the same bus terminal as the one I prepared for the NVG108 it just works fine. I get a steady bus led and can connect and program an individual address to alle modules. Just not this TOKKA one.

• When I push the program button, the red lights up (no flashing, but keeps steady red)
  • Unfortunately, ETS is not able to reach that part of the bus, it does not see the device in programming mode so cannot download the physical address.

This behaviour is quite exceptional for me, and I get no response from Tokka (not on the telephone numbers, nor on the e-mail). Do they still exist?

Anyone an idea what can be wrong, what can I try to get this working?
Someon even suggested trying reverse polarity on the Gateway, but I don't feel confident doing so ;-)

Any help really appreciated.

regards,
Steven