I'm using the KW41Z and have connected a digital magnetic Encoder KMA36 via I2C. When I do the initialization, I send several times 4 Bytes via I2C. In some cases I get an error Status_I2C_Addr_Nak from the RTOS function I2C_RTOS_Transfer(). Attached you'll find a trace from the I2C communication. There you can see that the clock for the NAK is missing.
The controller has integrated I2C modules. How can this occur?