Latency using HQPlayer Embedded (hqplayerd)

[stefano_mbp]

Thanks
…. maybe I misunderstood that this section was closed …. Sorry for the confusion

[simoncn]

As I said in my post about this, the MinimServer 2 forum section is closed for new threads but it is still possible to post replies to existing threads.

[simoncn]

In my test environment (RPi3 for server and RPi4 for renderer, 16/44 FLAC files, no transcoding), the great majority of the delay between tracks that causes these gaps is within HQPlayer (specifically, within the Rygel UPnP stack that HQPlayer uses to enable it to act as a UPnP renderer). Because HQPlayer doesn't use the UPnP gapless protocol, any significant delay during track changing breaks gapless playback.

If HQPlayer is running on a faster machine, renderer track-changing delay will be reduced and any server delay will come into play. Increased resolution and/or server-side transcoding will increase server delay.

The only way to make this work correctly in all cases is for HQPlayer to implement the UPnP gapless protocol. This enables the renderer to start streaming the next track before the current track has finished playing.

[stefano_mbp]

Thank you Simon for your analysis, I hope something to solve this issue will be done by Jussi

[stefano_mbp]

Hello Simon,
finally Jussi decided to put his hand to the implementation of the upnp gapless and fixed the way in which HQPlayerd and Rygel interact, now SetNextTransportURI works as it should and the gapless works, even with transcoding activated. This is a wonderful goal!
But it only works with PCM files, with DSD (dsf) files the gapless issue remains open.
Is there in Minimserver (or in upnp implementation) any difference between the way to manage PCM and DSD files?

[simoncn]

There shouldn't be any difference between PCM and DSF. I will contact Jussi to ask him for a test build that includes the new support.

[stefano_mbp]

Hello Simon, a brief follow up
the issue with native DSD files was due to the LAN throughput, I discovered that the HQPe pc was on a 100Mb/s branch, I moved it to a 1Gb/s branch and everything started working as it should …
Therefore, thanks to this setting, I can now say that HQPe and Minimserver, especially with regard to gapless, can work together combining the best of both

[simoncn]

Thanks for the update. I have been trying the HQPlayer gapless support but I have not yet been able to get it working correctly. My next attempt should be later today.

[stefano_mbp]

if it can help, I used the HQPlayerd OS image ver. 4.26.2 on a Nuc10i3 booted from usb stick.
To have the best result, no clicks or pops playing DSD native files/albums, you should create in
/etc/default a new file named hqplayerd (using nano editor, already available) and write inside
HQPLAYER_RESET_SDM=0 … (0 is a zero)
then save and reboot, that’s all.
The “chain” I’ve used is
Lumïn app - HQPe - Bubbleupnpserver - Minimserver - NAA/RoPieee XL/raspberry pi4 … dac usb …

[simoncn]

I don't have a Intel machne that is capable of running HQPlayer Embedded, so I am running it on a Raspberry Pi 4. I am using HQPlayer 4.26.2 and mconnect with the gapless protocol enabled. With this setup, there is a long gap between tracks. I have done a network trace which shows this gap is caused by internal delays within HQPlayer while preparing to stream the next track.

It seems HQPlayer works better on an Intel machine than a Raspberry Pi 4 for some reason. As this is now working for you, I don't intend to pursue it any further.