TAS2780: I encountered an error, but do not know how to solve it

Hi,

Pls make sure the hardware connection is fine. Then use following commands:

i2cdump -y -f 0 0x38
0 is i2c bus no
0x38 is 7-bit i2c device address

One more thing, what the 7-bit i2c address on your device? It seemed 0x70, this address is so strange, 
kindly check the datasheet and hardware engineer.