How to transform vsti audio data that can copy to asio buffer and make correct voice?

Question

I am trying to make sounds with vsti and asio. I have already transfrom the midi event to vst event, and then call the "processReplacing" function to make the vsti audio stream like this:

float *inputs[64];

float *outputs[2];

.....

m_effect->processReplacing(m_effect,inputs,outputs,m_blockSize);

but when I copy the "outputs" data to asio buffer, it make a noise.

memcpy (asioDriverInfo.bufferInfos[i].buffers[index], outputs[index], m_blockSize);

is the vsti audio data need any transformation before copy the asio buffer? I will be very appreciated, if you help me！