This is coming from a jrCore_logger() call where you've set the 3rd "debug" param to a debug log entry - you really should never get this as the value for log_log_id is the autoincrement value from the logs table, so it will always be unique - double check that the module is not trying to insert into that table directly.
There are no third parameter jrCore_logger calls in any of the modules, and nothing custom done to logging at all.
You said in your email that this was preventing you from creating xtSong items on the demo. If that is the case, I would look at any changes made to the modules since my last commit, as they were all working well at that point.
Is it this same error which prevents you from being able to create media on your localhost dev setup?
-- ¯\_(ツ)_/¯ Education, learning resources, TEL, AR/VR/MR, CC licensed content, panoramas, interactive narrative, sectional modules (like jrDocs), lunch at Uni of Bristol. Get in touch if you share my current interests or can suggest better :)