Loud pop sound is heard when starting up Rock

I heard a loud pop sound when starting up Rock with my DAC already powered up as well as my power amps. I observed from the screen monitor, it happens when loading RoonOS. It is nasty pop sound that can damage the speakers if the volume control is left too high.

My system: i5 intel NUC with 64GB SSD, 4GB RAM. Storage from NAS. My DAC is Holo Spring R2R DAC. There’s no issue when playing music; both PCM and DSD.

I noticed when I boot up Rock, the display of Holo Spring DAC initially start up shows ‘DSD512’ it change after if I start to play. If I use Windows OS, the initial start up sample shows on the display is ‘44.1k’.

Looks like the issue is somehow being resolved, no longer hearing nasty ‘pop’ sound. Though I don’t see any flagged to support group but I’m glad I no longer experience this😀

Hi @support, looks like loud pop sound happens when I do a reboot on ROCK via IP web. There’s a switch from 44.1k to DSD512 (shown on the display) on the Holo Audio Spring DAC during the reboot cycle.

If the amp is connected and volume control is left high, it will probably fry your expensive speakers! Can anyone look into this issue and have it fix?

Yes I have had this problem. It seems that for some reason the audio interface is initializating to DSD and then playing an PCM and then switching to something else to make the DAC swicth to the correct format makes a loud pop when the DAC “Thinks it is playing DSD” and then switch to something else. For me it worked to always play a first track with DSD prior to playing any PCM … Yes a pain in the behind but better than heart-stoping pops. I thought this was related to the overall DSD problem with Chord DACs but maybe it is not only Chord DACs.

Maybe this is not exactly like your problem but maybe the “root-cause” is the same.

I encountered this way back when Roon started supporting native DSD playback. The problem with native DSD is the program need to insert ‘0x69’ a digital silent code instead of sending 0x00 as in the case in PCM. DSD will output full negative voltage when the DAC is input with 0x00, basically all ‘0’, that will resulted in a nasty pop sound. If you amp’s volume is set too high, it will probably fry your speakers.

This happens when switching from PCM to DSD or when playing DSD is interrupted. It is important that program need to insert 0x69 to prevent nasty pop.

In my case, when ROCK boot up, the display of my DAC shows ‘44.1k’ after a few seconds it shows ‘DSD512’, there’s where the nasty pop occurred. I think the fix is simply default it to PCM 44.1k or DSD when boot up. Once is fully operational, users can always playback DSD where the program will insert 0x69.

This is case when I use Windows OS together with Roon. I don’t have nasty pop when boot up my PC.