Verhalten des Mic Input Bits
----------------------------

Bits:
	EAR_IN_MASK			0x40		

	MIC_OUT_MASK		0x08
	EAR_OUT_MASK		0x10		


EarOut	MicOut	=>	EarIn
-------	-------		----------------------------------------
	1		1	=>	Always:  1
	1		0	=>	Always:  1

	0		1	=>  Signal:  0/1
					Silence: Threshold depends on PCB issue.
							 Issue 2: 1; 4A: rnd noise; 6U: 0 (bzw: 110000000000000000000…)
							 others not yet tested

	0		0  =>	Signal:  0/1	with high amount of "0"
					Silence: 0