I lost one of the ear cushions of my insignia head phones

what --the dog or the head phones
the ear cushions may be difficult to get and it may be best to get new head phones
dogs you can get from the pound

The design of these headphones includes a microphone on the outside and on the inside of each earcup. The outside microphone detects outside noise. The inside microphone monitors what you are hearing and when it detects that the outside noise is present inside, the active noise-canceling circuits remove that noise. This happens fast enough that you perceive a significant reduction in the outside noise getting to your ears.

The airspace inside the earcup is a tuned chamber defined by the shape of the foam in the ear cushion. This is important because with the inside microphone in close proximity, but at a 90-degree angle to the speaker, the circuit must be designed to eliminate the normal feedback that occurs.

If the foam in the ear cushion has weakened/deteriorated to the point that it no longer has it's original shape, (in particular the lower half of the ear cushion), the size and shape of the air chamber inside of the earcup is directing more of the speaker sound toward the microphone than the design can compensate for causing audio feedback to occur. You are hearing that feedback.

On my QC-3 headphones, I can cause the feedback squeal in both earcups, with the left earcup being more sensitive to the shape change than the right.

It is probably time to replace the ear cushions. If so, they are available from Bose for $35/pair.

QuietComfort 3 Acoustic Noise Cancelling Headphones Bose Product Support

They are also available aftermarket at Amazon.com for $16.99/pair
Replacement Earpad ear pad Cushions For Bose QuietComfort 3 QC3 Headphones...

or $5.69/pair.
Bluecell Pair of Replacement Earpad Ear Pad Cushion for Bose Quietcomfort...

The ear cushions are held on the earcup with six snap fasteners, three on each side. To remove the ear cushion, simply pull it away from the earcup carefully so that you do not break the plastic snap tabs.

It should not be necessary to pry the ear cushion off with a sharp object, but if you do, be careful. There is also a thin gasket seal between the earcup and the ear cushion, take care not to damage it.

If you need to replace the ear cushions with new ones, they are available from Bose for $35/pair.

QuietComfort 3 Acoustic Noise Cancelling Headphones Bose Product Support

They are also available aftermarket at Amazon.com for $16.99/pair
Replacement Earpad ear pad Cushions For Bose QuietComfort 3 QC3 Headphones...

or $5.69/pair.
Bluecell Pair of Replacement Earpad Ear Pad Cushion for Bose Quietcomfort...

Please follow the proper instructions below

Ear cushion reattachment
If the ear cushions come off your headphones,
reattach them as follows:
1. Fit the mounting flange inside the rim of the ear cup.
2. Make sure it attaches smoothly and uniformly within the entire ear cup. (Do not remove the ear cup lining material).

Ear cushions may need to be replaced due to normal wear and tear. To order replacement ear cushions, call 1-888-865-2700.

Hope you are satisfied with my solution.Your valuable feedback would be appreciated.Thanks for choosing Fixya.

TinuAlbinAlex

Here:
http://www.jntworld.com/catalog/index.php?cPath=21_1002&currency=gbp&osCsid=c5b2f0de48c59564afb36dfebba513ac#tabbed_box_1

The ear cushions are attached to the earcup with plastic tabs that snap into the plastic in the earcup. The lower snaps may be unfastened. Try pressing the ear cushion firmly to the earcup around the lower edge to refasten the snaps. Do not press in the middle of the ear cushion - you may damage the internal microphone.

If this fails, you will need to remove the ear cushion by pulling it off the earcup and inspect for broken plastic where the tabs are on the ear cushion or where the tabs attach to the earcup. If a tab is broken on the earcup, replacement earcups are available from Bose for $35 per pair.

http://www.bose.com/controller?url=/shop_online/headphones/noise_cancelling_headphones/accessories/qc3_earcushionkit_acc.jsp

If the plastic in the earcup is broken, you can try to repair it or you can contact Bose about getting it repaired or replaced.

Yes a firm on E-Bay sells the cushions.

just buy somemore ear cushions and put them on your 360 headset. should be sold at radioshack. don't try wal-mart cause they wont sell any there.

There are some small silver inserts on the side of each earpiece. You can pry them off (gently) starting under the cushion and working your way around.

You can then remove the old cushions and put in the replacements and snap these silver retainer inserts back on.

You can get replacement cushions online for about $16.

It should be easy - I just eased mine out by pulling on the top and bottom parts of the headphone cushion/pad.

Hope that helps