This mod is janky. Do not attempt this if you don't feel at least decently comfortable with using a soldering iron near your iPod's parts.

Here's my attempt at designing an iPod back case replacement that allows for Bluetooth functionality without sacrificing the hold switch functionality. It's not elegant, but it works!

The case is designed to hold two generic toggle switches for hold functionality and Bluetooth power, as well as a push button recessed in the case for pair functionality.

This mod is largely reversible. While it requires soldering multiple wires to the headphone jack, hold switch, and the battery itself, in theory, the mod can be reversed by simply desoldering the wires or replacing the hold switch/headphone jack assembly and the battery. All parts in the front of the iPod, including the logic board, will be untouched.

Should you do this mod?

Here's help for you to decide whether you would want to attempt this mod:

Pros

• Bluetooth can be toggled on and off using a hardware switch.
• Extra space allows for a larger battery and a Taptic Engine.
• Hold switch functionality and headphone jack will be preserved.
• Mod is reversible.
• Custom engraving on the back possible.

Cons

• Screws won't do; all components are glued in using hot glue.
• iPod feels very lightweight, since it's missing the hard drive as well as the metal back.
• Less sturdy than the original back.
• Bluetooth quality will not be on par with wired audio quality.
• Soldering the components together is very finicky and potentially requires a lot of time (3+ hours in my case).
• It's not nearly as elegant as a moonlit.market Classic Connect Kit.

Print settings

I recommend printing the case at 100% infill, 0.2mm layer height, and with normal supports.
However, I printed it at 15% infill and removed supports from all the ports, leaving only the supports on the clips attaching the back to the front of the iPod. If you trust your printer with small overhangs and bridging, you can also leave out the supports on the switches, the headphone jack, and the 30-pin.

Components used

• Toggle switch for hold (Reichelt* // Amazon)
• Toggle switch for Bluetooth module power (BerryBase // Amazon*)
• 6x6x5mm push button (BerryBase // Reichelt // Amazon*)
• Bluetooth audio transmitter (AliExpress*)

Components marked with * are the ones I used, others are provided as compatible alternatives.

Further notes

• This will require a flash storage mod – I've used an iFlash Quad.
• Different battery sizes are possible. I've used a “2000”mAh battery. Of course, you can also use the original, but keep in mind the additional battery drain of the Bluetooth module.
  • This might also require you to wrap the battery's ribbon cable around itself. Be careful not the break the cable! I broke mine that way
  • Also make sure to route the wires from the battery to the Bluetooth module around the battery, not on top of it! Don't do what I did in the picture. Otherwise, there likely won't be enough clearance for closing the iPod.
• My Bluetooth module transmits electric interference noise to my headphones when not playing anything. This is largely inaudible when playing audio, however.
• The clips attaching the back to the front look small and fragile, but they will hold! I've even successfully removed and re-attached the back several times without damage to the clips. However, since they're less sturdy than the metal clips in the original case, the back will detach much more easily when dropped.
• Keep the original hold switch in the unlocked position (towards the ribbon cable, not away from it). Else, the iPod will be permanently locked and the toggle switch you attached won't do anything.
• For creating a custom engravement, I recommend embedding your motive by 0.4mm (two layers) into the back and using two different colours. Be sure to remove support material from the engraving! It likely isn't needed.
• As an added bonus, if you're using a transparent faceplate, the LED of the Bluetooth module will shine dimly through the top clip above the LCD screen if the module is placed as shown in the photo. This omits the need for an extra status LED.
• View the last picture for a basic diagram of how to connect the components. View Parts Plus Pods' video at 4:45 for the headphone jack wiring. You won't need the plastic part attached to the bottom of the headphone jack.
• Unlike Parts Plus Pods, I deviated from the hold switch wiring: connect the wires to the leftmost and rightmost pins, respectively, not the middle pin. Unlike shown in the video, DO NOT CUT THE RIBBON CABLE OFF THE HOLD SWITCH. They only do this because they're using the hold switch as a Bluetooth toggle; we have separate toggle switches for this, and thus, we want to preserve the hold switch assembly.

Credits

dianexis' original iPod back replacement was the basis for creating my back cover. Without it, I would have gone mad trying to figure out the dimensions and the spacing of the clips.

Parts Plus Pods' video on adding Bluetooth to your iPod was crucial in the making of my mod. I recommend watching through the entire video before attempting such a mod, they give good advice throughout the video.