B737 TAXIED FOR DEP AT ORD AS GND CTL USED WRONG CALL SIGN FOR CLRNC.

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CALLED CLRNC AND THEY SWITCHED US OVER TO GND CTL 121.75. AFTER A BRIEF WAIT; GND SAID TO US TO FOLLOW AN ACFT OFF GATE X. HE MAY HAVE CALLED US AABC; BUT WE WERE THE ONLY ACFT PUSHED THAT WAS IN A POS TO FOLLOW GATE X ACFT. CALL SIGN SOUNDED LIKE AAAB; BUT WAS GARBLED. GND WAS A RAPID FIRE NON-STOP TALK ON GND AND THERE WAS NO CHANCE TO CORRECT OR CLARIFY. SINCE WE WERE ONLY ONE IN POS TO FOLLOW HIM; DID SO AS TO NOT MISS OUR SEQUENCE. A LIKE CALL SIGN UNKNOWN TO US WAS ALSO ON FREQ AND WAS AABC; NOT AAAB; WHICH WE WERE. EACH GND XMISSION WAS GARBLED AND SOUNDED TO US LIKE AAAB; BUT COULD HAVE BEEN AABC. WELL; HE WAS CALLING US AABC AND WE DIDN'T GET A CHANCE TO CLARIFY UNTIL END OF RWY. TWR CLRED AABC FOR TKOF AND WE THEN CLARIFIED WITH HIM. HE WAS SURPRISED BUT NO PROB; AND GAVE US CLRNC FOR TKOF WITHOUT HESITATION. AABC WAS A FEW ACFT BEHIND US. THIS IS AN ONGOING PROB ON 2 ACCOUNTS: LIKE CALL SIGNS THAT ARE TOO CLOSE; AND 2) THE MOST IMPORTANT IN MY OPINION; NO CHANCE FOR AN ACFT TO READ BACK ANY CLRNC. THEY ARE RAPID FIRE AND THIS IS VERY DANGEROUS DUE TO CTLR DOESN'T EVEN KNOW IF WE RECEIVED IT; LET ALONE THE CORRECT RTE/HOLD SHORT INSTRUCTIONS. SUPPLEMENTAL INFO FROM ACN 616876: OBVIOUSLY WE TAXIED ALL THE WAY TO RWY 22L WITH THE MISTAKEN BELIEF THAT ATC WAS TALKING TO US WHEN IN FACT THEY BELIEVED THEY WERE ISSUING CLRNCS TO ANOTHER SIMILAR CALL SIGN ACFT. THERE WAS AN FAA SAFETY INSPECTOR ON THE JUMP SEAT WHO WAS ALSO UNAWARE OF THE CALL SIGN MIX UP. CONTRIBUTING TO THIS SIT; THE DISTR OF SEVERAL MINOR MAINT ISSUES JUST BEFORE DEP WITH AN FAA INSPECTOR ON BOARD.