Audio Amplifier
SIP9 +------+ ++ 1| Input | 2| GND (small signal) | 3| Muting | 4| Return 1 | 5| Return 2 | 6| GND (large signal) | 7| Exit Output 2 | 8| Exit Output 1 ++ 9| Vcc +------+
No frequency to check
M51516 Datasheet