https://devzone.nordicsemi.com/f/nordic-q-a/102511/using-internal-rc-with-nrf-connect-zephyrHi, We have a custom board that removes the 32 kHz crystal, so trying to enable the internal RC. I&#39;ve looked through similar issues here, and seems like what&#39;s needed in the prj.conf is: CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC =y However, I don&#39;ten-USTelligent Community 13Mon, 07 Aug 2023 06:43:08 GMThttps://devzone.nordicsemi.com/thread/440043?ContentTypeID=1Mon, 07 Aug 2023 06:43:08 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2026fb9e-2cab-49e7-8578-c07d00f07366SwRa<p>Hi sang,</p> <p>Glad to know that this has been resolved.</p> <p>Regards,</p> <p>Swathy</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/439767?ContentTypeID=1Thu, 03 Aug 2023 17:14:16 GMT137ad170-7792-4731-bb38-c0d22fbe4515:371a0361-5883-4c63-8835-3f22e19dfd4asangpark<p>after twiddling around with a bit more - it seems like our problem isn&#39;t related to the config setting, but resetting the custom board - which has other jigs on it, too.&nbsp; Complete power cycle after flash (with image built with CONFIG_CLOCK_CONTROL_NRF_K32SRC_RC=y) work as expected.</p><div style="clear:both;"></div>