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I pulled the firmware chip, and grounded pin 13.  The hiss was still there.  The output had reverb on it btw.

So I touched up the solder joints, again, and looked it over with my magnified phone app.  I didn't see anything that stood out as a problem.  Hiss is still there.

Yeah, I talked to the vendor.  It's not supposed to sound like that.  He suggested an audio probe, which led me to find out I have a clean input and a hiss on the output of the FV-1 chip.  Which led me to ask the question in this thread about tracking the audio through the FV-1 chip.

I bought the kit of parts from the vendor.  He soldered the FV-1 chip on for me, and provided me the firmware chip (along with the other parts).

I've already reflowed the solder joints, but I'm going to check again.  I'm used to working on tube amps, and these connections are tiny....

The pedal is setup so that it is hard by-passed with 3PDT.  No hiss.  When you engage the pedal, you can turn on reverb/chorus/boost in any combination, or no effect at all.  When the signal is going thru the FV-1 I get hiss no matter which effects are activated or not activated.

Just so I understand, if I'm getting hiss on pin 28, why would any components after that make a difference?

I'm building a Jed's Peds More!More!Moore! pedal.  This is a reverb/chorus/boost pedal using the FV-1 chip.

https://www.jedspeds.co.uk/product-page/more-more-moore

I've got it built and working, and it sounds great.  However, there is a fairly loud hiss that acts as a noise floor that really makes it hard to use.  The hiss is there regardless of whether the fx are engaged or not, and the hiss doesn't change when the guitar volume is at 10 or zero.  Kicking on the boost makes it a bit louder, but not much.

I've been building pedals and tube amps for years, so I know how to use an audio probe.  However, I've never built a pedal using the FV-1 chip.  I'm used to following the audio thru the circuit in a linear fashion, but it's not clear to me how the audio flows inside the FV-1 chip.

Using the audio probe, I have no hiss on pin 1 (input), and I have hiss on pin 28 (output).  It's hard to put the probe on the leads of the FV-1, but so far I haven't been able to find any audio on the pins to check for hiss.  Any tips on which pins (and components) to look at for the source of the hiss?

Here's a link to the schematic....