recorderbox 6 playlists

Curious are you using the Cloud sync feature or is this on a single Rekordbox DB?  

yes i am using recorderbox dj 6 cloud sync i dont know if its a bug bug my playlists are doubleing and triple i hope they fix this or i did something wrong has anybody come across this and to fix this

Technically you shouldn't be able to do anything wrong.  I have been testing for over three weeks with a MacBook Pro (primary device), Windows 10 machine and iOS device. I'm ONLY making edits on primary and watching secondary devices I've only made minor edits on secondary to see if they sync back to primary, 99% of work is done on primary. I have the following issues:

1. Sometimes deletions don't sync, I use a temp playlist when importing new tracks from there I assign to various playlists, after I'm done I clear out the temp playlists, sometimes changes don't sync.
2. Similar to above I've had a previous session sync back to the temp playlist like from 3 imports back < this one is especially weird, example I imported on following dates 04/01, 04/08, 04/15, 04/22, 04/29, on last import 04/29 emptied temp playlist sync to other devices fine, next day other devices now have the 04/15 tracks that were remove two sessions prior 
3. When rapidly adding songs to other playlists from temp playlist some tracks don't sync 
4. When rapidly adding songs to other playlists from temp playlist some artwork for the tracks don't sync
5. Whole playlists sometimes don't delete meaning if choose to completely remove it

The sync issues are "consistent" on the secondary devices meaning whatever problem I see on Windows machine I see on the iOS device. First time I had the sync problem of #1 I tested using WiFi sync of iOS to sync back to MacBook this resulted is merging all changes.  This also is especially troublesome.  Granted it is a safe approach to make sure no data is lost but imagine the scenario where you just spent the past two weeks reorganizing your library only to find out your iOS device is not consistent with the main device and do the WiFi sync you could lose two weeks of work and be in worse condition than you started because of the merge.  There needs to be a way to say I know Device A is correct and push that out as the master database.  

I have not seen your issue yet but I've stopped testing and went back to 5.8.5.  Messing up my playlists is too scary.  BTW check your rekordboxagent log for errors in the log.log.  You may need an advanced editor to open my log is already > 250MB.  After a certain size you need notepad++ to open. If that doesn't work you may need VIM to open.  On Mac log can be found here:
/Users/<username>/Library/Application Support/Pioneer/rekordboxAgent

Windows:
C:\Users\<username>\AppData\Roaming\Pioneer\rekordboxAgent

In the Windows log I found that every time there is a bad sync like mentioned above I see following in the logs:
[200423T205533.088-0500] E/sync SequelizeDatabaseError: SQLITE_CORRUPT: database disk image is malformed
at Query.formatError (C:\Program Files\Pioneer\rekordbox 6.0.0\rekordboxAgent-win32-x64\resources\app.asar\node_modules\sequelize\lib\dialects\sqlite\query.js:423:16)
at Statement.afterExecute (C:\Program Files\Pioneer\rekordbox 6.0.0\rekordboxAgent-win32-x64\resources\app.asar\node_modules\sequelize\lib\dialects\sqlite\query.js:119:32)
at Statement.replacement (C:\Program Files\Pioneer\rekordbox 6.0.0\rekordboxAgent-win32-x64\resources\app.asar\node_modules\@journeyapps\sqlcipher\lib\trace.js:19:31)
at Statement.replacement (C:\Program Files\Pioneer\rekordbox 6.0.0\rekordboxAgent-win32-x64\resources\app.asar\node_modules\@journeyapps\sqlcipher\lib\trace.js:19:31)
[200423T205533.088-0500] E/sync Error occured in SyncManager#process

BTW their developer does not know how to spell occurred :).

I've also had a few RB Crashes on my Mac those logs can be found here:
/Users/<username>/Library/Pioneer/rekordbox/Exceptions

Other I believe related issues are very sluggish performance when skipping around previewing tracks.  I finally tracked it down to the RB Agent.  If I pause it performance returns to normal when previewing tracks.  They suggested it was Buffer set too low which I tested and seemed to improve but came back.  Ultimately found out buffer has no affect because I could have excellent performance with buffer back to original setting.  The problem seemed to go away the last few days of testing.  I have a theory that its related to another issue I found in the RB Agent log:
[200421T075413.596-0500] E/sync UnknownEndpoint: Inaccessible host: `lambda.eu-west-1.amazonaws.com'. This service may not be available in the `eu-west-1' region.
at Request.ENOTFOUND_ERROR (/Applications/rekordbox

I saw a few instances of that and I think the agent was going crazy trying to reconnect to the cloud server.  Additionally I saw a credential problem which also may contributed to the issue:
[200418T024621.010-0500] E/routes/api/data/djmdCues/update_item SequelizeUniqueConstraintError: Validation error
at Query.formatError (/Applications/rekordbox

I have two tickets open one for CPU performance and one for Cloud Sync issues.