ZAB CTLR DESCRIBED INCIDENT WHEN INCORRECT READ BACK WAS MISSED; ACFT GIVEN TO ANOTHER CTLR; AND POTENTIAL CONFLICT DEVELOPED.

Narrative

ACFT #1 WAS ISSUED A PLT'S DISCRETION DSCNT TO FL360 AND HANDED OFF TO THE HIGH SECTOR. AFTER REVIEWING TFC; ACFT #1 WAS TOLD TO AMEND ALT; DSND NOW; MAINTAIN FL360. THE ACFT READ BACK FL260. THE ACFT WAS THEN SHIPPED TO THE NEXT SECTOR WHERE THERE WAS TFC (ACFT #2) AT FL350. I BELIEVE PART OF THE CONTRIBUTING FACTOR IS THE RADIOS ON THE SECTOR. THEY ARE CONSTANTLY BEING TURNED ON FOR PERFORMANCE ISSUES AND ONLY BEING RESET INSTEAD OF REPLACED. THE PLT'S XMISSION WAS FULL OF STATIC. SECONDLY; IN MY UNDERSTANDING OF THE 7110.65; WHEN I NEED TO REMOVE A PLT'S DISCRETION DSCNT; I NEED TO STATE 'AMEND ALT' WHICH I FEEL THE PLT IS ASSUMING A NEW NUMBER; NOT REMOVAL OF DISCRETION. AS FAR AS HUMAN FACTORS; THE CLRNC WAS ISSUED TWICE TO THE ACFT; ONCE AS PLT'S DISCRETION WHICH WAS READ BACK CORRECTLY; THEN THE REPEAT OF PLT'S DISCRETION; WHICH WAS NOT READ BACK CORRECTLY; CAUSING SOME COMPLACENCY. ALSO; PRIOR TO THIS ACFT; THE SAME CLRNC WAS GIVEN TO ANOTHER ACFT IN THE SAME ORDER WITH THE SAME ALTS; ALSO LNDG ELP. SO IT HAD BEEN THE FOURTH TIME IN A ROW TO HEAR THE SAME READBACK.