Pop before start of a few songs in playlist

Listening to a playlist of songs from various sources (with various sample rates) will, on occasion, result in a soft “pop” immediately before a song begins. I’m using a Pi 3 with a Hifi Berry DAC+ hat (common 5v power). There are a number of settings (such as sample rate conversion, processing settings, conversion filter, and resync delay) - would any of these affect the issue? I have resync delay set at 1.5 seconds now - and will try doubling that and see what happens.

Hi @Ronald_Lyster,

I’m not sure this is the best place to ask that question. I assume you’re running RoPieee, but it might be a better idea to ask this in the hardware section.

That said: yeah, a lot of settings can influence something like this. At least you should provide the basic information that people will ask for anyway:

  • what source material? PCM? DSD?
  • which sample rates?

And then I’m afraid you need to narrow it done and try to find a reproduction scenario.

Hopes this helps a bit.

Thanks again, Harry. I guess the reason to post here is that I had no such pops when I was using a Squeezebox Touch. Is that a possiblde clue to what is happening?

Hi @Ronald_Lyster,

Roon (and RAAT for that matter) is a totally different technology than the good old Squeezebox.
That means that the issues you have can be a lot of different things.

The only way to figure out what’s going on is trying to dissect and dismiss things piece by piece.
A good place to start would be to figure out if there’s a setting in which everything works as expected.

So, disable upsampling (if used), try to narrow it down to source material format and sample rates first.


Will do and thanks again.

By the way, is there a single Roon resource to explain fully each setting? If not, that certainly would be helpful to someone like me who is looking to tweak these settings.

Here’s your “problem child” (me) back again. I’m still trying to conquer this popping problem. It only occurs on the HifiBerry Dac+ zone, and I am now confident that it occurs only upon a change in sampling rates. I have a test playlist that has a 44.1kHz track followed by a 192 kHz track, followed by another 44.1 kHz track, etc. Changes from the higher sample rate to the lower rate will cause a “pop” every time. (Some pops are louder than others.)

I have tried a 5s resync delay, limiting sample rates to 48kHz, limiting PCM to 16, and limiting the maximum sample rate to DSM64. (I did not reboot or restart the core after changing these settings - need I do so? I did not combine any of these changes.) None of these changes made any difference at all in the popping noise.

Hi @Ronald_Lyster,

These kind of pops are probably related to the HAT you’re using.
What you can try is to set the ‘Resync Delay’ value in Roon. It’s used by Roon when switching sample rate to give the device a little bit of time to synchronize to the new sample rate.

Good luck!

As I mentioned, I have tried a 5s resync delay - didn’t help. Have you had any other experience with the Hifi Berry DAC+ doing this?

No not personally. I don’t have that one.

What you could do, and it’s a bit of a ‘hack’, is use upsampling to have everything send out with the same samplerate.

That sounds like a good idea. How does one do that?
BTW, I just put in a request to Hifi Berry’s tech support.

Go to audio setup, and then choose ‘DSP Engine’.
There you’ll see a tab called ‘Sample Rate Conversion’.

It can be quite intimidating, so give me a poke when you need some more assistance.

Certainly appreciate your help on this. I see what you mean by intimidating… Now that I have enabled sample rate conversion, what do you suggest for all the other settings - smooth / precise / linear / minimum / parallelize / native DSD processing??? Not to mention the sample rate itself (DSD? / Custom? PCM? PCM power of 2?)

No, you should use PCM (the Hifiberry doesn’t do DSD afaik), and select the highest bitrate it can do (96k?), so that’s ‘MAX Pcm Rate’.

I would leave the processing settings for what they are right now.

That seems to have worked. I’ve run my “test” playlist, which would always produce those pops before, and no pops now. Should I play with the other sample rate conversion “tweaks,” or just leave good enough alone?

Ok good to hear.

Wrt the other settings: that’s purely personal taste, but I think that Roon’s ‘out-of-the-box’ settings are very decent.

Enjoy the music!