Due to problems populating the analog pattern in generate_analog_pattern, the analog signals generates a "glitch" every 40ms.
Created attachment 63 [details] The glitch
Patches on the mailing list: http://sourceforge.net/mailarchive/forum.php?thread_name=1390768258-19857-2-git-send-email-poljar%40poljar.org&forum_name=sigrok-devel Please give them a go.
This was fixed in 9d156555a557aa079056d42fbc9ddd12338e842e.