Hi Rob, I experienced sounds like that in the past, but not on the BCD-1.
IMO this was because of bad conversion software. Like converting mp3 to wave or another format to wave. The pops would occur randomly on discs. When I change to a better software converter the problem went away. Another thing that caused occasional glitch was cheap cd-rs. Also if I play a cd that was copied from a copy protected disc, I usually get static on the last track. Some cd's can't be copied at all, but it's rare to encounter one of those. Some cd's can be copied but the sound is degraded from the original, but those are rare as well.
So I have to ask the question, do you know if these discs you played were converted?