The file contents are as follows; SoftDevice Assert: PC - 0x00018664, Line Num - 430, File name - ll\src\ll_lm.s0.c, 2.90. I use a Garmin heart rate monitor and Tempe. Have been running software version 4.20 although the error has been present for the last two updates. Just in the process of upgrading to 4.30.