LNDG PATTERN ALT CONFUSION TWR FLC COM.

Narrative

WE WERE CLRED FOR THE VOR/DME A APCH AT TEB BY APCH CTL. AFTER WE CONTACTED TEB TWR WE WERE CLRED; 'DSND TO 1500 FT AND CROSS THE VOR AT 1500 FT.' ONCE WE CROSSED THE VOR; PF ENTERED A L DOWNWIND FOR RWY 19 AND STARTED A SLOW DSCNT. AT 1200-1300 FT MSL THE TWR CTLR QUESTIONED US ABOUT OUR ALT. REPLY: 'AT 1200-1300 FT.' TWR: 'CLB BACK TO 1500 FT AND MAINTAIN 1500 FT UNTIL FURTHER CLRNC.' WHILE CLBING BACK TO 1500 FT I SAW AN ACFT PASSING UNDERNEATH ON FINAL FOR RWY 24. TWR CAME BACK AND TOLD US THAT THE PREVIOUS CLRNC WAS TO DSND TO 1500 FT; CROSS THE VOR AT 1500 FT AND MAINTAIN 1500 FT. I REPLIED THAT WE ONLY WERE TOLD TO DSND TO 1500 FT AND CROSS THE VOR AT 1500 FT. BOTH PLTS ADMIT THAT WE ONLY HEARD THE DSCNT AND CROSS PORTION OF THE CLRNC AND NOT THE MAINTAIN 1500 FT PART. BUT WE ALSO HAVE TO ADMIT THAT WE COULD HAVE MISSED THAT PART DUE TO THE HIGH TFC AND HIGH RADIO TFC ON THE TWR FREQ. WE DEFINITELY DIDN'T LEAVE AND WON'T LEAVE AN ASSIGNED ALT UNLESS WE ARE CLRED TO DO SO OR UNLESS WE BELIEVED THAT A/THE PREVIOUS CLRNC PERMITS US TO DO SO. CTLR WAS VERY SPECIFIC WITH HIS CLRNC FOR TFC FOLLOWING US. PROB: HIGH TFC VOLUME; HIGH TFC VOLUME ON THE FREQ; MANY WAYS TO GET DISTRACTED AT A BUSY ARPT AND TFC FOR RWY 19 AT 1500 FT ON DOWNWIND FOR RWY 19 WHILE TFC ON FINAL FOR RWY 24 LOWER THAN 1500 FT (PROBABLY 800- 1200 FT). THAT IS ASKING FOR TROUBLE EVEN WHEN EVERYTHING AND EVERYBODY WORKS TOGETHER AS CLRED BY THE CTLR.