DLNA plugin - only parts of the functionality working with my client

[bitstream]

I got a DLNA client A, a Synology DLNA server and a JF DLNA server. Both server are currently running in parallel while I'm testing JF with the intention to replace the Synology.

Testing with music media, Synology is supporting the whole functionionality the DLNA client is offering: Browsing, play, stop, pause, next, previous, reapeat modes, random, loading cover picture. Interestingly on JF only browsing, play, stop, pause, loading cover picture are working.

I was assuming that next, previous, reapeat modes, random are client functionality which have nothing to do with the DLNA server. Same for Random and Repeat modes. Form the observed behaviour, this does not seem to be the case, it seems the DLNA server is involved somehow (wasn't able to find more information about this yet).

Before i start digging deeper, does someone know if

• this indeed is server side functionality?
  
• if this is supported by the DLNA plugin and known to be working?
  
• In case it is supported, where I could have missed something/why this is not working in my installation?
  

My next steps would be to

• try to find a DLNA specification
  
• tcpdump ing the communication
  

[bitstream]

Two more interesting observations from the same client:

- The directory/file listing on JF is significantly slower than on the Synology, although JF has far more CPU power and RAM available.

- While on Synology album images are loaded once and displayed, the same client when connected to JF always loads album images 5 times, leading to a flickering display (i can see 5 http requests for the image from the client). Interestingly the request parameter (image id) is changing it time, although it's always the same image being displayed. I guess this is another indication something in the communication between client and JF is not working as it should.

I will try with another client aswell, maybe it's an interoperability problem.

[bitstream]

After testing a bunch of combinations of clients with my two servers, it seems JF DLNA is a bit "picky" - some clients are working without issues (i.e. VLC, others have problems with limited functionality. The Synology Media Player is working with all clients I have tested without problem.

I couldn't find out why this is nor if the clients are implemented differently. I.e. I can imaging "next" could be implemented differently: It could be a "relative" command sent to the server, unstructing the server to play the next song in an album, but it also could be the client just stopping the current song and sending a play command for the next song in the song list the client has received before. I haven't tracked this down in detail, so I don't know if this is about different implementions. Fact is, JF DLNA is not fully working with every client.

--

Have to correct myself: VLC isn't fully working with JF. Browsing is buggy, listing does only work for "genres" and "albums", all other categories fail to list. So no browsing of trees and folders... Maybe it's a timeout problem? 420 Interpreters isn't that much, that should be read from an index within fractions of a second....