Serial_LTE_Modem application requires reset after power on

When using the serial_lte_modem application on a custom nrf9160 board I have discovered that I get nothing out of the UART unless I pull VEN low and then release it (reset the chip.)

At this point I get "ready" and then can use whichever AT commands to get my desired results without any problem.

Why might this reset be required with the serial_lte_modem example but not at_client?


For further information I have VDD set to 3.7V and VDD_GPIO set to 3.3V. VDD comes up first and pulls VEN with it through 10K. I have also tried setting VDD and VDD_GPIO both to 3.3V. In this configuration they come up at the same time but I still have to pop a reset before I can begin communicating with the nrf9160 running this application. 

Also I am using GPIO 1 and 0 for UART2. I have used 1 and 0 for UART0 and configured the application accordingly and had the same results.

I am on the latest NCS 1.3.1

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