That's too bad, it doesn't seem to be able to buffer 24 bit very well, I get stutters in the first 10 seconds of most songs, and it's definitely not my delivery path or internet speed.
I also had trouble playing 24-96 and 24-192 files via BubbleUPnP server. I thought it was a BubbleUPnP problem and wrote to them and attached the logs. I received this answer:
"The log shows that your Gustarender is becoming
unresponsive to UPnP commands just after being instructed to play a 96 kHz / 24-bit FLAC from MinimServer.
It is possible its
FLAC decoder has a problem with HiRes (assuming you can play 44.1/16 FLAC fine).
If you set "Audio decode is PCM for: All audio formats + constraints below" this makes BubbleUPnP Server
convert input audio to WAV (with no loss of quality)
so this would workaround any eventual flaw in the HiRes FLAC decoding of the Gustarender."
So I logged in via SSH to R26 and when playback was stuttering, memory usage was at 100%, this is what I saw in mpd.log:
"alsa_output: Decoder is too slow; playing silence to avoid xrun"
I updated mpd player to the latest version but the result was even worse.
With Media Render configuration in BubbleUPnP "Decode Audio to PCM for: All audio formats + constraints below" HiRes flac files play without stops but there is a problem with DSD playback because DSD64 files are decoded with a sampling frequency of 352kHz, DSD128 with 764kHz and DSD256 files are up to 1.4MHz and this is too high. In addition, information about decoding the DSD file is not displayed and the 1-bit decoder will not work.
I haven't used Roon yet but installed it on a Synology DS220+ and I'm surprised how it plays. R26 uses about 50% of memory and plays HiRes flac and DSD without problems. A special application inside the R26 streamer - Roon Bridge, made rather by Roon programmers, is responsible for playback. It works perfectly!
I also tested Tidal connect, it uses a lot of memory but it works.
If Roon is not in use it is possible to disable Roon Bridge and save 30MB of RAM.
Additionally, I found that in upmpdcli.conf you can enable Open Home Renderer. This is a compelling advantage because you can use (e.g. BubbleUPnP, Linn Kazoo, Linn app…) without a BubbleUPnP server.
Theoretically, Gustard could prepare two versions of the update: one for Roon users and the other for non-Roon but Tidal users, etc.
After all this, I even bought a Munich M1T but eventually returned it because for the same money or even less I will buy a lifetime Roon license and I will not need a separate streamer.
I have the impression that the R26 streamer is designed especially for Roon. Further updates will not bring any improvement other than Tidal connect, maybe memory consumption will be optimized, but I do not expect significant major changes.