The Bose QC2 is part of a line of headphones made by the Bose company. The "QC" stands for "Quiet Comfort." The QC2, no longer in production, is an older version of the QC15, an around-the-ear fitting headphone. If you experience problems with your Bose QC2 headphones, you can try these troubleshooting tips to repair them before contacting the manufacturer for help.
Change the battery on your headphones. You'll know if you need to replace the battery because the "low power" light on the right earpiece will begin flashing when less than five hours of battery life is remaining. Locate the battery compartment, which is on the side of the right earpiece (this is the earpiece with the power switch). Pop the protective plastic lid off the earpiece and remove the old battery. Bose suggests replacing the old battery with a new AAA alkaline version. Insert the new battery and close the chamber.
Turn the unit on by flipping the power switch (located on the right earpiece) forward. If the headphones are still not working, take the battery out of its chamber and flip it around (so its positive and negative ends are facing the opposite direction). The headphones will not work if the battery was inserted improperly.
Check the connection to your outside music source. This connection can be made by plugging a cord connected to a device such as an MP3 player or laptop into the bottom side of the left earpiece. Bose warns that if the plug is not pushed in to the left earpiece all the way, the resulting audio may be unclear or nonexistent. Bose encourages the use of the connection cord that came with your QC2 purchase, as other cords may fit improperly or result in poor-quality audio.
Examine both earpieces to make sure the earcup cushions are properly attached. Because the QC2 features an around-the-ear fit, any problems with the cushions can cause a change in audio quality. Carefully inspect the inside and outside rim of the cushions to make sure they are connected to the headphones; the cushions attach to the headphones at eight points on each earpiece. If one of the connection points has become disconnected, use your fingers to slip it back on. Torn cushions should be thrown away (or returned to Bose if your headphones are still under warranty) and replaced with new cushions.
Wipe down any dust, debris or moisture on the outside of your QC2 headphones with a dry cloth.
Re-fit the headphones to your ears. Bose reports that a low, rumbling sound may be caused by a poor fit and not by any problems with the headphones. For a best fit, make sure the ear cushions completely surround the ear (you should not be able to see any part of the ear).
Return your headphones to Bose for repairs or a replacement. This service is free if your headphones are still under warranty. Bose features a limited warranty on its products and urges owners to check the box in which they purchased their QC2 headphones for details for its terms of conditions. You can call Bose at 800-999-2673 or e-mail customer service at firstname.lastname@example.org for information specific to the problems you are experiencing with your headphones.
Do not expect to hear any audio or music from the headphones unless you plug them into an outside source, such as an MP3 player. The Quiet Comfort line by Bose features noise cancelling technology. The Bose QC2 headphones also can be connected to in-flight audio options on an aeroplane; however, Bose cautions that this audio may not be of the best quality. Any problems involving audio quality or volume while connected to an airport system may be due to the audio source and not the headphones.
If you choose to connect your Bose QC2 headphones to a music source, make sure you do not turn the audio too high. Bose recommends avoiding long-term exposure to extreme volume to prevent hearing damage or loss.