Computer is 3.5 gHz. AMD Ryzen Quad-Core, 384KB of L1 cache, 2.0 MB of L2 and 16 or L3.
In today's CWTs, I experimented with increasing RadioSwap Transmit Tail and Lead Times. Lead time was previously set to 30 and the Tail time was 100. Changed them both to 200 and didn't have any problems, though need to test more before I feel secure that this solves the issue (as it's intermittent).
Thanks for pointers.