ACFT ABORTS TKOF TWICE ON SAME RWY.

Narrative

FLT XX FROM HOU TO DFW WAS HOLDING SHORT OF RWY 12R AT HOU. THE TWR CTLR CLRED US INTO POS ON RWY 12R TO REMAIN W OF RWY 17. AS OUR ACFT LINED UP ON RWY 12R WELL W OF RWY 17; A DIFFERENT TWR CTLR CLRED US FOR AN IMMEDIATE TKOF. TFC WAS CLRED TO LAND ON RWY 17. THE FO ADVANCED THE THROTTLES AND THE TKOF WARNING SOUNDED STABILIZER. THE FO RETARDED THE THROTTLES. I RECHKED THE SETTINGS AND SEEING NOTHING ABNORMAL; THE THROTTLES WERE ADVANCED AGAIN AND AGAIN THE WARNING SOUNDED. THE ACFT WAS STILL WELL W OF RWY 17. I INFORMED TWR TO CANCEL OUR TKOF CLRNC. TWR ORDERED US TO HOLD OUR POS AND ADDED THAT WE SHOULD NOT ACCEPT TKOF CLRNC UNLESS WE WERE READY TO GO; AND THAT HE DID NOT HAVE A PLACE FOR US TO GO. KNOWING THERE WAS ARRIVING TFC AND NOT KNOWING THEIR EXACT POS; I DECLARED AN EMER TO ALERT EVERYONE OF THE SIT. AFTER REDIRECTING SOME ACFT; TWR CLRED US TO THE W RAMP. WE WERE ABLE TO RESET OUR SYSTEMS AND SOLVE THE PROB. WE CANCELED THE EMER AND DEPARTED HOU. UPON ARR AT DFW MAINT WAS NEEDED TO ADJUST THE TKOF WARNING LIMITS. POSSIBLY I COULD HAVE INCLUDED MORE INFO WITH THE FIRST TWR CONTACT AFTER THE WARNING OCCURRED.