I tried to use the UPnP-plugin with my Freecom Musicpal but after playin' for around a minute or so it just stops playin'. I looked into the log myself but it didn't tell me anything, so maybe you'll have a look?
2; 1 Initialise - 09.11.2015 14:22:50
22; 2 GetNetworkAddresses - 192.168.251.30,dns=True,name=Ethernet,speed=1000000000
23; 3 GetNetworkAddresses - 192.168.56.1,dns=True,name=VirtualBox Host-Only Network,speed=1000000000
23; 4 GetNetworkAddresses - 127.0.0.1,dns=False,name=Loopback Pseudo-Interface 1,speed=1073741824
24; 5 GetNetworkAddresses - http://192.168.251.30:49382
15699; 6 Profile - Generic Device, useragent=pvConnect DLNADOC/1.50
16282; 7 ProcessMessage 192.168.251.23 - device 'uuid:56076f6e-6b79-4d65-641e-0001db096372:MusicPal',valid=True
16287; 8 Profile - Generic Device, useragent=Freecom MusicPal|Linux/2.x.x, UPnP/1.0, pvConnect UPnP SDK/1.0, TwonkyMedia UPnP SDK/1.1
16289; 9 Profile - Generic Device, useragent=Freecom MusicPal|Linux/2.x.x, UPnP/1.0, pvConnect UPnP SDK/1.0, TwonkyMedia UPnP SDK/1.1
16349; 10 Activate - MusicPal:http-get:*:audio/mpeg:DLNA.ORG_PN=MP3;DLNA.ORG_OP=11DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/mp3:DLNA.ORG_PN=MP3;DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/x-mpeg:DLNA.ORG_PN=MP3;DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/L16;rate=44100;channels=2:DLNA.ORG_PN=LPCM;DLNA.ORG_OP=01;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/L16;rate=48000;channels=2:DLNA.ORG_PN=LPCM;DLNA.ORG_OP=01;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/L16;rate=44100;channels=1:DLNA.ORG_PN=LPCM;DLNA.ORG_OP=01;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/L16;rate=48000;channels=1:DLNA.ORG_PN=LPCM;DLNA.ORG_OP=01;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/x-wav:DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/wave:DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/wav:DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/x-m4a:DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/mp4:DLNA.ORG_PN=AAC_ISO;DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/mp4:DLNA.ORG_PN=AAC_ADTS;DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/x-aac:DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000,http-get:*:audio/x-ms-wma:DLNA.ORG_PN=WMABASE;DLNA.ORG_OP=11;DLNA.ORG_FLAGS=8D100000000000000000000000000000
19845; 11 Play - stream (http://192.168.251.30:49382/encode/continuousstream-2147483644.L16)
19954; 12 Profile - Generic Device, useragent=pvConnect DLNADOC/1.50
19955; 13 Profile - Generic Device, useragent=pvConnect DLNADOC/1.50
19956; 14 GetEncodedFile[1] 192.168.251.30 - HEAD to 192.168.251.23; mime=audio/L16;rate=44100;channels=2,rate=44100,channels=2
19971; 15 Profile - Generic Device, useragent=pvConnect DLNADOC/1.50
19972; 16 Profile - Generic Device, useragent=pvConnect DLNADOC/1.50
19973; 17 GetEncodedFile[2] 192.168.251.30 - GET to 192.168.251.23; mime=audio/L16;rate=44100;channels=2,rate=44100,channels=2
20164; 18 StateTimer - Loading,old=Stopped
21168; 19 StateTimer - Playing,old=Loading
80713; 20 NetworkChange_NetworkAddressChanged -
80742; 21 GetNetworkAddresses - 192.168.251.30,dns=True,name=Ethernet,speed=1000000000
80743; 22 GetNetworkAddresses - 192.168.56.1,dns=True,name=VirtualBox Host-Only Network,speed=1000000000
80744; 23 GetNetworkAddresses - 127.0.0.1,dns=False,name=Loopback Pseudo-Interface 1,speed=1073741824
80745; 24 GetNetworkAddresses - http://192.168.251.30:49382
81691; 25 GetEncodedFile[2] - exit=10054, playtime=61715
81743; 26 SyncNewPlayState - Stopped,mb=Playing
81774; 27 NetworkChange_NetworkAddressChanged -
81790; 28 GetNetworkAddresses - 192.168.251.30,dns=True,name=Ethernet,speed=1000000000
81791; 29 GetNetworkAddresses - 192.168.56.1,dns=True,name=VirtualBox Host-Only Network,speed=1000000000
81792; 30 GetNetworkAddresses - 127.0.0.1,dns=False,name=Loopback Pseudo-Interface 1,speed=1073741824
81793; 31 GetNetworkAddresses - http://192.168.251.30:49382
82964; 32 SsdpServer:SendNotifyMessage - Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
host=192.168.251.30,nt=upnp:rootdevice,usn=11687931-39e7-47fc-b72b-10cbc9921d12,isalive=True
83016; 33 SsdpServer:SendNotifyMessage - Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
host=192.168.251.30,nt=11687931-39e7-47fc-b72b-10cbc9921d12,usn=11687931-39e7-47fc-b72b-10cbc9921d12,isalive=True
83068; 34 SsdpServer:SendNotifyMessage - Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
host=192.168.251.30,nt=urn:schemas-upnp-org:device:MediaServer:1,usn=11687931-39e7-47fc-b72b-10cbc9921d12,isalive=True
Don't know what changed, but it's working now after removing the Musicpal temporarily due to renovation. In case anybody else is having these symptoms please be sure to pull the plug of your receiver and wait 5 minutes :-)