Narrative:

Sector was busy with multiple rdu departures wbound; clt departures eastbound and multiple arrs to both gso and rdu from the south. Also numerous aircraft overflying the sector between 110 and 150 plus the BE9L at FL200 on a route (sbv-sav) that conflicted with all departure and arrival rtes. Supervisor was plugged in giving an over the shoulder check. Because of the jack he was in I lost foot pedal capability. I began using the ptt button on my headset. Shortly after air carrier X crossed my boundary I issued a descent clearance so I could get him under aircraft Y. Nothing transmitted. After a few attempts to get my microphone to key up I realized the ptt was dead. I then swapped jack position with the supervisor and regained foot pedal capability. I quickly switched two aircraft and then reissued the descent clearance to aircraft X. Aircraft X did not start his descent for 3 radar updates and then only descended 100 ft on each of the next 2 radar hits. The next radar hit conflict alert activated. Aircraft were approximately 8 mi apart head on. I expedited his descent through FL190 and called traffic to aircraft Y. Both pilots saw the other aircraft. My headset failure causing me to play 'catch up' distraction me from my scan and the slow descent caused this error to be unavoidable. I also do not know if uret flagged this situation when I entered a lower altitude in the data block of aircraft X. D-side training was in progress but they were on a handoff line.

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Original NASA ASRS Text

Title: ZDC CTLR EXPERIENCED OPERROR AT FL200 BECAUSE OF LATE CORRECTIVE ACTIONS; I.E. FAILING TO REALIZE TRANSMITTER FUNCTIONALITY LIMITATION.

Narrative: SECTOR WAS BUSY WITH MULTIPLE RDU DEPS WBOUND; CLT DEPS EBOUND AND MULTIPLE ARRS TO BOTH GSO AND RDU FROM THE S. ALSO NUMEROUS ACFT OVERFLYING THE SECTOR BTWN 110 AND 150 PLUS THE BE9L AT FL200 ON A RTE (SBV-SAV) THAT CONFLICTED WITH ALL DEP AND ARR RTES. SUPVR WAS PLUGGED IN GIVING AN OVER THE SHOULDER CHK. BECAUSE OF THE JACK HE WAS IN I LOST FOOT PEDAL CAPABILITY. I BEGAN USING THE PTT BUTTON ON MY HEADSET. SHORTLY AFTER ACR X CROSSED MY BOUNDARY I ISSUED A DSCNT CLRNC SO I COULD GET HIM UNDER ACFT Y. NOTHING XMITTED. AFTER A FEW ATTEMPTS TO GET MY MIKE TO KEY UP I REALIZED THE PTT WAS DEAD. I THEN SWAPPED JACK POS WITH THE SUPVR AND REGAINED FOOT PEDAL CAPABILITY. I QUICKLY SWITCHED TWO ACFT AND THEN REISSUED THE DSCNT CLRNC TO ACFT X. ACFT X DID NOT START HIS DSCNT FOR 3 RADAR UPDATES AND THEN ONLY DSNDED 100 FT ON EACH OF THE NEXT 2 RADAR HITS. THE NEXT RADAR HIT CONFLICT ALERT ACTIVATED. ACFT WERE APPROX 8 MI APART HEAD ON. I EXPEDITED HIS DSCNT THROUGH FL190 AND CALLED TFC TO ACFT Y. BOTH PLTS SAW THE OTHER ACFT. MY HEADSET FAILURE CAUSING ME TO PLAY 'CATCH UP' DISTR ME FROM MY SCAN AND THE SLOW DSCNT CAUSED THIS ERROR TO BE UNAVOIDABLE. I ALSO DO NOT KNOW IF URET FLAGGED THIS SITUATION WHEN I ENTERED A LOWER ALT IN THE DATA BLOCK OF ACFT X. D-SIDE TRAINING WAS IN PROGRESS BUT THEY WERE ON A HDOF LINE.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.