Excuse the double post but somebody that loves you very much Taratx, explained the situation further via PM. Please correct me if I am wrong but I understand the situation thus:
Dark Initiate has CG LED with Obsidian Lite setup (originally from Spectre)
Spectre became a stunt (LED only) setup temporarily
Then your Fulcrum (originally RGB LED with V3 sound) was gutted to become a stunt now
And the Emerald and V3 sound were installed on the Spectre. Li-on batteries and everything.
Issue needing troubleshooting:
The Spectre with the Emerald and V3 sound newly transplanted into it, tested out just fine. It sounds like you soldered and heatshrinked and assembled everything back up after satisfactory testing. Then you connected the Emerald Board to your computer to change the color. And based on what you are saying also connected the V3 to change the font. Then you experienced issues keeping the saber on while connected to your computer? Which you temporarily solved by just swapping in fresher batteries to maintain it will you programmed it.
Then while connected to the EMERALD BOARD from the computer, the sound coming out of the speaker became barely audible. (Question, did you keep the same speaker that came with the Emerald and V3 sound board setup and that is what is installed in the Spectre now, I assume YES?)
Question, have you tried setting the color back to what it was to see if maybe the new amp draw to the LED is somehow not providing the speaker enough juice compared to what you tested? This should not be the case but I am curious if reverting back to like say a just red LED (lowest voltage) setting helps out with volume? This would then lead me to check the resistors on the LEDs, did all those get kept when you installed the RGB onto the Spectre. Otherwise I guess you could be drawing more current than what you need to the LEDs and starving the speaker or vice versa maybe you did blow the speaker but in that case I would think setting it to red LED would still cause almost inaudible sound. There might be a clue in trying this.
Like I said I don't have an answer as I don't have experience with hands on wiring of sabers and boards, just book wormingly absorbing what I read on these threads.
My guess after looking into this so closely my head hurts, is that there was a short somewhere. When you kept swapping in the new batteries to force it to continue working while reprogramming, it overloaded and blew your speaker. So actually I think you have stated your own answer in the end, but maybe somebody else has experienced this and can chime in to solve the mystery.
Thank you for your help!
As of today new speaker setup is installed and sound is working. I cut out all my connections and redid them incase something wasn't perfect, but thinking I'm gonna leave as is just incase. I've got my pulse set from DVA, to an aqua blue. And everything is working as of now.