[Android Apps and Games] coolchillies:
Hi, after some fiddeling around i decided to post my problem.

On my raspberry pi 3 (debian stretch) BubbleUPnP server is working flawlessly. So i know the installation procedure on my part is correct. Not on the RPi 4 though. I pulled the log from /root/.bubbleupnpserver/. The lines have been truncated but I hope this is enough. Btw i'm using Qobuz for streaming.

[main (1) ] INFO - 45:37:40.593 - .d : added Renderer device: gmediarender on raspberrypi
[main (1) ] INFO - 45:37:40.694 - .a : gmediarender on raspberrypi: volume range: 0..100
[main (1) ] INFO - 45:37:40.698 - .a : gmediarender on raspberrypi: supports SetNextAVTransportURI: true
[cling-59 (GetProtocolInfo) (100) ] WARNING - 45:37:40.748 - .l : bad SOAP XML response: org.fourthline.cling.e.b.j: Can't transform message payload: org.fourthline.cling.b.a.c: The argument value is invalid. Invalid number of input or output arguments in XML message, expected 2 b$
[cling-59 (GetProtocolInfo) (100) ] WARNING - 45:37:40.751 - .Main$b$1 : bad action SOAP xml: device exception: org.fourthline.cling.e.b.j: Can't transform message payload: org.fourthline.cling.b.a.c: The argument value is invalid. Invalid number of input or output arguments in XML messa$
[cling-59 (GetProtocolInfo) (100) ] WARNING - 45:37:40.755 - .d : GetProtocolInfo: Error: Current state of service prevents invoking that action. Error reading response message. Can't transform message payload: org.fourthline.cling.b.a.c: The argument value is invalid. Invalid num$
[main (1) ] WARNING - 45:37:40.757 - .a : gmediarender on raspberrypi: cannot get ProtocolInfo: org.fourthline.cling.b.a.c: Current state of service prevents invoking that action. Error reading response message. Can't transform message payload: org.fourthli$
[main (1) ] INFO - 45:37:40.759 - .a : gmediarender on raspberrypi: hasSetNextPlayItem: true, supportsSetNextPlayItem: true
[main (1) ] INFO - 45:37:40.760 - .a : gmediarender on raspberrypi: AVTransport eventing enabled: false
[main (1) ] INFO - 45:37:40.762 - .b : gmediarender on raspberrypi: TransportState: Stopped
[main (1) ] INFO - 45:37:40.767 - .e : started subscription callback for service (n) ServiceId: urn:upnp-org:serviceId:RenderingControl
[main (1) ] INFO - 45:37:40.772 - .ac : started task GetTransportStateTask: gmediarender on raspberrypi
[cling-55 (96) ] INFO - 45:37:40.782 - .g : Established subscription uuid:dad9e2e4-fc05-11e9-9c06-e9415e790a01 on service (n) ServiceId: urn:upnp-org:serviceId:RenderingControl of device (l) Identity: (m) UDN: uuid:6e1c16b52152d03b51157e35ec78ab87, Descriptor$
[cling-56 (GetTransportInfo) (97) ] WARNING - 45:37:40.798 - .l : bad SOAP XML response: org.fourthline.cling.e.b.j: Can't transform message payload: org.fourthline.cling.b.a.c: The argument value is invalid. Invalid number of input or output arguments in XML message, expected 3 b$
[cling-56 (GetTransportInfo) (97) ] WARNING - 45:37:40.801 - .Main$b$1 : bad action SOAP xml: device exception: org.fourthline.cling.e.b.j: Can't transform message payload: org.fourthline.cling.b.a.c: The argument value is invalid. Invalid number of input or output arguments in XML messa$
[cling-56 (GetTransportInfo) (97) ] WARNING - 45:37:40.804 - .d : GetTransportInfo: Error: Current state of service prevents invoking that action. Error reading response message. Can't transform message payload: org.fourthline.cling.b.a.c: The argument value is invalid. Invalid nu$
[GetTransportStateTask: gmediarender on r] WARNING - 45:37:40.805 - .ac : GetTransportStateTask: gmediarender on raspberrypi: org.fourthline.cling.b.a.c: Current state of service prevents invoking that action. Error reading response message. Can't transform message payload: org.fourthline$
[main (1) ] INFO - 45:37:40.864 - .OpenHomeService : protocolInfo: ,tidalhifi.com:*:*:*,qobuz.com:*:*:*,http-get:*:audio/x-ms-wma:*,http-get:*:audio/x-aiff:*,http-get:*:audio/x-dff:*,http-get:*:audio/x-dsf:*,http-get:*:audio/x-dsd:*,http-get:*:audio/L16:*,http-get:*:a$
[main (1) ] INFO - 45:37:41.718 - .QobuzClient : Qobuz login: device id: null, username: present, user id: present, userAuthToken: present, lossless: true, lossy: true, hires streaming: true, hires purchases streaming: true, mobile: true
[main (1) ] INFO - 45:37:41.719 - .CredentialsService : SequenceNumber: 1
[main (1) ] INFO - 45:37:41.774 - .a : gmediarender on raspberrypi: AVTransport eventing enabled: false
[main (1) ] INFO - 45:37:41.775 - .a : gmediarender on raspberrypi: time task polling interval: 900ms
[main (1) ] INFO - 45:37:41.777 - .b : gmediarender on raspberrypi: enabled gapless: true
[main (1) ] INFO - 45:37:41.778 - .b : gmediarender on raspberrypi: detect external stop: false
[main (1) ] INFO - 45:37:41.779 - .CredentialsProvider : qobuz: audio quality: 27
[main (1) ] INFO - 45:37:41.780 - .CredentialsProvider : tidal: audio quality: LOSSLESS
[main (1) ] WARNING - 45:37:42.297 - .CredentialsProvider : qobuz: no compatible codec found
[main (1) ] WARNING - 45:37:42.298 - .CredentialsProvider : qobuz: no compatible codec found
[main (1) ] SEVERE - 45:37:42.299 - .b : FIXME: org.fourthline.cling.b.a.c: no compatible codec found
[main (1) ] INFO - 45:37:42.324 - .a : SetNextAVTransportURI(qobuz://track?version=2&trackId=69727661, <DIDL-Lite xmlns="urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/" xmlns:upnp="urn:schemas-upnp-org:metadata-1-0/upnp/" xmlns:dc="
[main (1) ] INFO - 45:37:42.345 - .b : rewriteUrlMetadataFFmpegTranscode: com.bubblesoft.upnp.utils.didl.a
[main (1) ] INFO - 45:37:42.358 - .AVTransportService : GAPLESS: setNextAVTransportURIAction: qobuz://track?version=2&trackId=69727661
[main (1) ] INFO - 45:37:42.360 - .OpenHomeService : gmediarender on raspberrypi (OpenHome): next playback item position: 1
[main (1) ] INFO - 45:37:42.496 - .d : gmediarender on raspberrypi (OpenHome): loaded playlist: /root/.bubbleupnpserver/Playlists/dd9b4358-b648-f0a3-0000-00003ed5f6ff.dpl
[main (1) ] WARNING - 45:37:42.657 - .CredentialsProvider : qobuz: no compatible codec found
[main (1) ] WARNING - 45:37:42.658 - .CredentialsProvider : qobuz: no compatible codec found
[main (1) ] SEVERE - 45:37:42.659 - .b : FIXME: org.fourthline.cling.b.a.c: no compatible codec found
[main (1) ] INFO - 45:37:42.664 - .a : SetNextAVTransportURI(qobuz://track?version=2&trackId=69727661, <DIDL-Lite xmlns="urn:schemas-upnp-org:metadata-1-0/DIDL-Lite/" xmlns:upnp="urn:schemas-upnp-org:metadata-1-0/upnp/" xmlns:dc="
[main (1) ] INFO - 45:37:42.668 - .b : rewriteUrlMetadataFFmpegTranscode: com.bubblesoft.upnp.utils.didl.a
[main (1) ] INFO - 45:37:42.679 - .AVTransportService : GAPLESS: setNextAVTransportURIAction: qobuz://track?version=2&trackId=69727661
[main (1) ] INFO - 45:37:42.680 - .OpenHomeService : gmediarender on raspberrypi (OpenHome): next playback item position: 34
[main (1) ] INFO - 45:37:42.681 - .d : gmediarender on raspberrypi (OpenHome): track id: 34
[main (1) ] INFO - 45:37:42.683 - .d : gmediarender on raspberrypi (OpenHome): shuffle: false, repeat: false
[main (1) ] INFO - 45:37:42.690 - .d : created OpenHome device: gmediarender on raspberrypi (OpenHome)

I guess there's some issue with Cling, but my knowledge about BubbleUPnPServer and the inner workings is none to zero to do some debugging on my own.