...rabbitin' on about Air Traffic Control again...

Whenever I remove my Noise-Cancelling, David Clark headset I become completely deaf for hours afterwards...
All I can see are peoples mouths moving...but no sound..!!!
It takes AGES for the effects to gradually wear off...!

Is this a common occurrence when using noise-cancelling headsets...?

Cheers all...!

Paul...(Another reason for going deaf.....(as well as blind)...........!
LOL...!

I wonder how it compares to, say, pulling your helmet off after a long ride on the bike.... I mean, how are the old jug-handles doing in general?  Anything else cause this problem? I SAID... ANYTHING ELSE... sorry.
  It's OK, we're all doctors here...

  Don't have any experience with them,but I've worked with active noise-cancelling and sound-masking rooms, and it's important to remember how this works:

ANR systems produce sound. It's the same sound as outside the "cans", only out of phase. Sure, the phasing leads to an overall reduction in noise levels, but it's not 100% efficient. Ill bet they sometimes produce an increase in gain; 180-degree phasing can sometimes produce spikes at certain frequencies when the waves overlap instead of cancelling each other out. In a moving plane, with noises changing all around you, it could happen, Ithink.
   Or am I wrong- do they really squash all the noise all the time? 
If you're cranking the headset's volume to hear the radio better, I think if you turn the receiver's volume up more and the headset's volume down a bit, you'll get more voice with less "masking" noise.
If you play with these two volume controls, you should find a sweet spot, where the masking is just barely cancelling-out the ambient din inside the plane, but you can hear the radio clearly.
Cleaning the ears occasionally helps, also... or maybe a trip to the barber. Where do I send the bill?

OK, i've done a little research, and I think my original theory is all wet:

I'd assumed the microphone part of the ANR system is outside the earcup, but it seems it's inside, so it should work very efficiently. I guess it's possible that it might then mistakenly supress a portion of the voice signal heard inside there, which might cause the user to turn them up, but I dunno.
It's possible, Fozz, that your problem has more to do with the changing air pressure effects on the ear, very common for pilots... it might seem to be caused by the ANR headset because you wear it every time you fly...?

We don't use them. I'm going deaf naturally!

Have you tryed flying with a regular, non-noise canceling headset?

Are these by any chance the BOSE noise canceling headphones?  If they are then do yourself a favor: disassemble the ear cups and you'll find a small hole in each of these.  Fill this hole with epoxy or something.  Put 'em back together and you'll find that they do a better job of blocking out sound. 

The BOSE system, though often well thought of, doesn't work as well as simple barrier type noise protection (simple, non-active headphones which block outside noise).  The company puts holes in the headphone cups to make the effect of the active supression more apparent.  You can hear sound (through those holes) with them turned "off" but the sound reduces when they're "on".  Filling the holes and leaving them "off" gives better noise reduction than produced by the headphones when "on".  You can try filling the holes AND turning on the active supression but I don't think you'll find that to be much of an improvement over simply filling the holes.

I know the pressure thing is pretty obvious, but tell Dr. Rotty more about this: do you ever experience "popping" etc. even at typical bug-smasher altitudes? Do you know the La Salve method for clearing the ears (hold nose and gently try to exhale thru nose, forcing air thru the Eustachian tubes)? Always works like a charm for me. And God knows when the pressure inside is built up it can cause a dramatic temporary loss in hearing.
You might want to try clearing your ears when you're going up and coming down, whether you feel the need or not. Yes, you might also clear them when you're going down , but that depends on the duration of your "dive"... ahem

An indicator that the temporary hearing loss is pressure-related will be if it clears up all of a sudden-like; this can go on for some time after landing before the pressure equalizes... especially if there's a lot of cobwebs, lint, etc. in there!!
My sinuses get so funky sometimes that I can go for hours after swimming or flying without my ears "popping" on their own, unless I clear them myself. As you probably know, the inner ear is cnnected to your sinuses and throat, via the E. tubes.
And you still haven't answered my question: even though it's quieter for you on your bike, do you ever have the same problem after a long ride?

Yeah, could just be that your ears don't like those cans; try a different pair and see. Just this quack's opinion...

I agree that they're sort of a nuisance. I often take mine off for a few minutes, if the situation allows... I've realized that the noise inside the plane isn't all that bad (although it sure seems that way when you first take off the headset!), but over time, it'll take its toll. And I have yet to hear a speaker in a Cessna that I could stand to use much for communications...

No doubt the range decreases with age (damn things just wear out, i guess) but if you're careful, you'll be able to avoid toting a big ear-horn around for a long time.
Last time I was tested I did OK up at the top of the scale, which is amazing considering I've worked in construction, a nightclub, recording studios, and played drums in rock bands for years, often foolishly not using any ear protection (ah, youth!)... but I do have a bit of tinnitis ("The bells! The bells! Sanctuary!"), and sometimes loud music will make my left ear do some very odd things (used to keep the monitor wedge on a box right by my left ear when playing drums- stupid!).  Fortunately, it's not intrusive (yet), and definitely is associated with stress, fatigue, and the occasional sinus-blockage.

As for pinching and blowing (sounds dirty, doesn't it?), absolutely must be done gently, better three or four gentle attempts than one big blast; and it works well for me to do this before I feel any discomfort- actually seems to help prevent it.
On the few SCUBA dives I've done, the rule was to more or less continuously "clear" on the way down as a preventative measure- very different  pressure differential than climbing to 1000-2000 feet in flight, but logic dictates the same rule applies, to a lesser degree. So in flight, I'll usually do it a couple of times whenever I'm going  up, and often when descending, especially if I've been cruising for a long time.
  On flights past 5000 I almost always sense the need to clear my ears at some point (although once in a while, I'll feel the pressure climbing or descending at much lower altitudes)... but yes, very gently.