External speaker amplifier makes loud pop when switching cores and turning on/off?

[sofakng]

I'm using a MiSTer in a custom arcade cabinet (ie. CRT TV with arcade controls, etc) but I'm using a car speaker amplifier connected to speakers.

Here is the setup:

MiSTer -> Extron SW4 VGA/Ars Switcher -> Volbox inline audio volume -> JBL DA4002 Amplifier -> 2x Speakers

Everything works perfectly except there is a loud pop when I turn the MiSTer on or off and when I switch cores.

I've searched for this issue and it sounds like it's common for car audio setups but the on/off relay typically turns the amplifier on or off before the stereo to prevent this.

Can anybody give me any advice or info to solve this problem?

[thorr]

Try running the audio directly to the amplifier to see if the problem is caused by any of the inline equipment. From what I recall, my MiSTer pops too, especially with my subwoofer turned on.

[retrodroid]

Are you using the analog audio jack on the IO board? The solution is to instead use the optical output (from the same port) and run it through a DAC.

See viewtopic.php?f=29&t=2049

[sofakng]

Thanks so much for the information ... That's the exact issue I'm having. I should have searched better before posting.

Did you find a DAC that eliminates the popping? You mentioned in that thread you still have the issue, but somebody commented later on recommending the FiiO D3?

EDIT: Jotego also seems to recommend this PROZOR 192KHz Digital to Analog Audio Converter DAC? (only $12.99 on Amazon)

[Doozer]

I confirm that the DAC is indeed removing the pop sounds between core loading.

I have also the PROZOR version and it works like a charm.

[bbond007]

Can anybody give me any advice or info to solve this problem?

From the old Atari MiSTer forum:

Different cores have different zero level making the capacitor charge at some level and then discharge when other core is loaded.

https://www.atari-forum.com/viewtopic.p ... 98#p354698