How to Fix the No-Sound Issue on Your Bose QuietComfort (QC) 35 I and II by Replacing the Speaker Driver (DIY Repair Guide)

Are your Bose QuietComfort (QC) 35 1st and 2nd Generation wireless Bluetooth headphones producing distorted or crackling audio, especially at higher volumes? If you notice reduced volume or complete sound loss on one side, the speaker driver may be damaged and needs to be replaced.

In this DIY Bose QC 35 I and II no sound repair guide, we will show you how to replace the worn-out left and right speaker drivers with new OEM spare parts at home.  Find the tools and genuine spares for this repair below.

Prefer a professional fix? Send us your Bose QuietComfort (QC) 35 I and II headphones using our mail-in repair service, and our repair ninjas will restore your device to peak working condition. You don’t need to pay upfront. We only charge after repairing your device.

Fill out our repair form to receive your free prepaid shipping label, then send your device. We’ll take care of the rest.

Repair Difficulty

Moderate / Requires 45-60 minutes to complete.

This repair involves handling small screws, delicate wires, and circuit boards.  While prior soldering experience helps, it’s not mandatory. With the right tools, a bit of patience, and attention to detail, you can fix the no-sound issue on the Bose QC 35 (1st and 2nd Generation) headphones by replacing the speaker driver yourself.

Replacement Parts You’ll Need

Restore your Bose QuietComfort (QC) 35 wireless headphones’ audio quality with original replacement parts. Select OEM spares from the drop-down menu below to restore your device to peak working condition.

• Bose QuietComfort QC45 QC35 QC25 I II 40MM Speaker Driver Cone Replacement - Parts

• Bose QC25 QC35 QC45 QC SE QC Headphones Repair Tool Kit – Complete Set

Looking for another spare part? Browse Joe’s GE Parts Catalog for genuine replacement parts for your Bose QuietComfort (QC) 35 headphones.

Tools You’ll Need

Before you start repairing the Bose QuietComfort (QC) 35 I and II speaker driver, gather the following tools. Using the correct instruments will help you complete the repair successfully. We used the following tools and recommend them for a safe, professional-quality DIY fix at home.

• 1.5mm Phillips Screwdriver
• 1.5 mm Flathead Screwdriver
• Precision Tweezers
• Nylon Spudger
• Soldering Iron
• Soldering Flux
• Heat Gun
• B7000 Adhesive
• Heat-Proof Anti-Static Rubber Work Mat
• Super Glue

Don’t want to DIY? Let our certified techs handle the repair. Book your repair now.

Step-by-Step DIY Guide to Replacing the Speaker Driver on the Bose QuietComfort (QC) 35 I and II Headphones Yourself

In this DIY repair guide, we will show you how to replace the blown left and right speaker drivers on the Bose QC 35 (1st and 2nd Generation) wireless headphones. Follow each step carefully and use the accompanying images as a visual guide to complete the repair with confidence.

The repair process is similar for both the left and right sides. We’ll point out any minor differences as we go.

Step 1: Extract the Earpad Cushions

1.1. Grab the earpad cushion with your hands and gently pull it out of the groove.

1.2. Two strips of double-sided adhesive tape secure the underlying mesh pad. Gently peel them and set the mesh pad aside.

1.3. Remove any old adhesive residue with a nylon spudger.

Step 2: Disassemble the Earcup

2.1. Unfasten two 2.0mm Phillips screws securing the earcup housing cover.

2.2. Flip the earcup. Insert a nylon spudger into the seam between the earcup and the housing cover, pry up till the cover separates, then set it aside.

2.3. Unfasten two 2.0mm Phillips screws from the AUX PCB and store them in one of the slots on the rubber work mat.

2.4. Peel the adhesive tape covering the AUX PCB connector with precision tweezers and store it carefully.

2.5. Peel the adhesive tape under the ribbon cable from the speaker cover and disconnect the smaller ribbon connected to the power button. The 1st Gen QC 35 headphones’ power button is on the earcup. You can skip this step when repairing that model.

Ninja Repair Tip: Bend the ribbon cable and tuck it under the earcup swivel arm to free up more space during the repair process.

Additional Steps for the Right Side

2.6. Pull the button off the PCB with precision tweezers.

2.7. Disconnect the ribbon cable from both ends and peel away the double-sided adhesive tape with a nylon spudger, then set the cable aside.

Step 3: Remove the Speaker Cover

3.1. Spread the speaker wires with your fingers and take a photo of the connections to use as a reference during reassembly.

Pro Tip: Remember that the red wire connects to the positive terminal, and the copper wire connects to the negative terminal.

3.2. Apply soldering flux to the red and copper wires and desolder them from the main board.

3.3. Set your heat gun to 200°F(93°C) at 70 air speed and heat around the edge of the speaker cover.

3.4. Insert a screwdriver into the small access port on the speaker cover and pry till the cover begins to separate. Do not yank the cover off the housing, as that will tear the speaker wires.

3.5. Once the cover has lifted enough for a soldering iron to slide inside the gap, desolder the speaker wires.

Essential Note: Because visibility is limited while desoldering the speaker wires, note that the copper wire is on top and the red wire is on the bottom.

Step 4: Extract the Faulty Speaker Driver

4.1. Apply heat uniformly around the edge of the faulty speaker driver to soften the underlying adhesive.

4.2. Insert a flathead screwdriver under the speaker driver and gently pry up till the speaker separates from the housing.

4.3. Scrape away any adhesive residue from the speaker housing using a flathead screwdriver.

Step 5: Install a New Speaker Driver

5.1. Apply 4 dabs of super glue around the perimeter of the speaker housing.

5.2. Grab a new speaker driver, align the connectors with those on the main board, and press down on the speaker till the super glue bonds.

5.3. Apply a thin line of B7000 sealant around the perimeter of the speaker driver.

5.4. Resolder the speaker wires to the main board. Connect the copper wire to the top and the red wire to the bottom position.

5.5. Apply 3 dabs of super glue on the rail on which the speaker cover sits. Apply a thin line of B7000 sealant on the rest of the rail to ensure the cover sits securely.

5.5. Align the speaker cover with the rail and press down so that the adhesive bonds.

5.6. Apply a drop of B7000 sealant around the wire where it meets the speaker cover.

5.7. Resolder the other end of the speaker wires to the PCB.

Additional Steps for the Right Side

5.8. Reinstall the button on the main PCB.

5.9. Plug in both ends of the ribbon cable, and press down on the center of the wire so that the double-sided adhesive tape bonds to the speaker cover.

Step 6: Reassemble Your Bose QuietComfort (QC) 35 I and II Headphones

Exclusive Step for the 2nd Gen QC 35: Reconnect the ribbon cable to the power button.

6.1. Align the AUX PCB with the hole in the earcup housing, then secure the PCB with two 2.0mm Phillips screws.

6.2. Pat down the ribbon cable so that the double-sided adhesive tape bonds to the speaker cover.

6.3. If the small round rubber piece fell out during any step, align the notch with the groove and push it into place.

6.4. Place the black adhesive tape over the AUX PCB connections with precision tweezers.

6.5. Install the earcup housing cover and secure it with 2 Phillips screws.

Step 7: Reinstall the Earpad Cushion

7.1. Cut 2 small strips of double-sided adhesive tape and place them over the speaker housing.

7.2. Peel off the protective layer and install the mesh pad for a secure grip.

7.3. Align the hooks on the earpad cushion with the groove on the earcup housing, then pull the hooks into the groove for a secure fit.

Congratulations! Your Bose QuietComfort (QC) 35 I and II Wireless Headphones are Ready to Use

You have successfully replaced the blown speaker driver on the Bose QC 35 I and II wireless Bluetooth headphones. Check audio quality, button response, charging stability, and Bluetooth pairing to confirm the device is working properly.

If you found this guide helpful and want to try DIY gadget repair, check out our store for essential tools and spare parts. You can also check out our at-home headphone repair guides for other popular brands, including Apple, Beats, Bose, and Sony.

Have questions or suggestions about this repair? Text a repair ninja or email us, and we’ll get back to you shortly.