RR250 Series compressor stall.
1/ ICE?
2/ Dirty Compressor? (Power check)
3/ Damaged compressor? (Power check)
4/ Bleed valve jet blocked or dirty - valve closes too soon?
5/ FCU acceleration schedule too high?
6/ Duplex Fuel nozzle?
7/ #1 turbine nozzle area / flow dimension? (Is your power check too good to believe)
Something ain't right. Stop and fix it.