Hue emulation fails

I’m trying to make Hue Emulation work in OpenHAB 2 but I have little success. I have set pairingEnabled=true and the Philips Hue app does find OpenHAB as a bridge but it refuses to connect to it instead giving a very unhelpful error message “The connection with the Bridge has been lost. Do you want to try again? Otherwise, tap Cancel to continue without a Bridge.”. When I check the debug log, I see the following:

14:14:22.552 [TRACE] [tion.internal.HueEmulationUpnpServer] - Got SSDP Discovery packet from
14:14:22.554 [TRACE] [tion.internal.HueEmulationUpnpServer] - Sending to : HTTP/1.1 200 OK
CACHE-CONTROL: max-age=100
SERVER: FreeRTOS/7.4.2 UPnP/1.0 IpBridge/1.10.0
ST: urn:schemas-upnp-org:device:basic:1
USN: uuid:5712f5da-5264-4a37-bce2-4321cea03ebc::urn:Belkin:device:**

However, I never see a request to /api/discovery.xml from this IP in the log. What is weird is that I DO see a request to /api/discovery.xml from which is my Mac.

Any ideas?