Effeciency update

Moved parameter update out of the audio callback - the code should be more efficient!

The attached bin file can be flashed to the pod via DFU using:

dfu-util -a 0 -s 0x08000000:leave -D grnltr_pod.v0.98.bin -d ,0483:df11

Replace grnltr_pod.bin with grnltr_bluemchen.v0.98.bin above for the bluemchen.