B757 FLT CREW WHILE HOLDING SHORT OF RWY BELIEVE THEY HAVE LOST COMS AND QUERY THE TWR.

Narrative

ON TAXI OUT; WE WERE SWITCHED FROM GND TO TWR; 132.22 NO MENTION WAS MADE TO 'MONITOR' FREQ. WE INITIALLY HEARD COMS ON 132.22; BUT THEN THERE WAS DEAD SILENCE ON THE FREQ FOR SEVERAL MINS. CONCERNED WE MIGHT HAVE A RADIO ISSUE; WE QUERIED 'RADIO CHK' AND GOT NO ANSWER. WE TUNED OUR SECOND VHF TO 132.22 TO ENSURE THE RADIO WAS WORKING. BY NOW; OTHER AIRLINES WERE ALSO QUERYING TWR; AS THE FREQ WAS UNUSUALLY SILENT. FINALLY; AFTER SEVERAL MINS; TWR RESPONDED RATHER IRRITABLY TO ANOTHER AIRLINE THAT WE WERE ALL SUPPOSED TO 'MONITOR THE FREQ;' AND HE WAS VERY BUSY. AN ACFT IN FRONT OF US CROSSED RWY 33L; AND YET WE HEARD NO CLRNC FROM 132.22 FOR HIM TO DO SO. ANOTHER AIRLINE; AGAIN; QUERIED TWR AND SAID; 'IS ANYBODY THERE?' TWR CAME BACK; EVEN MORE IRRITATED; AND ONCE AGAIN ADMONISHED US TO MONITOR. THIS AIRLINE REPLIED; 'WELL; WE SAW A GUY CROSS RWY 33L AND WE DIDN'T HEAR THE CLRNC; SO WE WERE WONDERING IF WE WERE ON THE RIGHT FREQ.' TWR REPLIED; 'HE GOT IMPATIENT AND SWITCHED FREQS BEFORE I TOLD HIM TO; THAT'S WHY.' THE DEAD SILENCE WHEN ONE IS HOLDING SHORT TO CROSS AN ACTIVE RWY LEADS TO THAT CREEPING FEELING YOU FORGOT TO SWITCH FREQS; OR SOMEHOW YOUR RADIO DIED; OR TWR HAD A PWR OUTAGE.