SDK 6.0.4 channel assignment for Max 6 problem

Hi, forum,
not sure what's wrong here, but when I do a simple channel check to input stereo and directly copy to output stereo with the new Max 6 dsp routine, something strange happens - When I play a stereo music in, the output stereo is a pseudo mono - same left/right channels of contents. Here's my code below:

// this is 64-bit perform method for Max 6
void myexternal_perform64(t_myexternal *x, t_object *dsp64, double **ins, long numins, double **outs, long numouts, long sampleframes, long flags, void *userparam)
{
t_double *inL = ins[0];
t_double *inR = ins[1];
t_double *outL = outs[0];
t_double *outR = outs[1];
int n = sampleframes;

// this perform method simply copies the input to the output, offsetting the value
while (n--) {
*outL++ = *inL++ ;
*outR++ = *inR++ ;
}
}

If I specifically zero the right channel out, it performs as expected, just i can't pass through a stereo signal as is... Anybody encounters the same issue?

Thanks!