Popping on speaker when power is low?

I've got my CF8 build working and it is amazing. Will probably do a Prizm next time just for ease of installation, but this was a great learning experience.

One thing I'm curious about, but a little context first. I tried getting away without soldering to a battery using *very* sticky copper tape to keep the wires in place (never soldered to a battery before, was a little apprehensive). But I was experiencing popping on the speaker due to the unstable ground connection, so I soldered the ground and that cleaned it up quite a bit. I did leave the positive alone for a while because it was harder to get to (and I was being lazy). But it was having charging issues due to false resistance I imagine (it would quit charging too soon) and so soldered the positive as well.

Dramatic difference after that, better amperage as evidenced by the brighter LED, and consistent charging. I used the saber quite a bit this weekend and its battery was getting low. The main way I noticed this was that the sound became quieter. Eventually, I started getting popping on the speaker again. I thought perhaps that the wires on the speaker were breaking off from the solder joints or something was up with the power/ground joints on the battery again. But I tried charging it first since I had used it a lot, and I still got a consistent charge, about an hour and a half. Powered it on after that and the popping seemed to be gone.

Should popping on the speaker happen when the battery is low?

Low battery is the cause of many quirky issues with sound boards. I'd double check your wiring connections to be sure, but if charging the battery fixed your problems, then that's the likely cause.

It's not unique to any particular model or manufacturer, something goofy will generally happen when the battery is low. You might also get things like false swings or with high draw pixel blades they may dim or not light completely and/or reboot.