stm32 fft results getting added

hi,

the project "arm_cortexM4lf_fft_bin_example" works fine immediate after reset,
that for first time. looping it with while(1),second time repeating the fft results gets added.

it continuing even after re initializing the input and output buffer pointers to zero location

arm_cfft_radix4_init_f32(&S, FFT_SIZE, 0, 1);
/* Process the data through the CFFT/CIFFT module */
arm_cfft_radix4_f32(&S, &Input[0]);
/* Process the data through the Complex Magniture Module for calculating the magnitude at each bin */
arm_cmplx_mag_f32(&Input[0], &Output[0], FFT_SIZE);

.

please help me to correct this.

Thanks in advance

Venugopal