Last week the internal scrobbling option in Deezer was lagging for several hours, see the main thread about scrobbling in this forum. So it is possible that this is the reason why you miss scrobbles. When Deezer caught up the queued scrobbles and submitted them later, they probably did not have the original timestamp anymore, but rather the one when they were submitted to your Last.fm user profile. So you can check your Last.fm library if you can find them anywhere.

To avoid problems with the internal Deezer scrobbling, you can also use external scrobbling apps, they are available for Android devices and the web player in a desktop browser.

Thank you @bluezzbastardzz! 

If you play ten tracks, maybe only seven will appear in listening history and get scrobbled to Last.fm.

Works fine when selecting individual tracks, but in a playlist, it will usually miss the fourth song, and then intermittently miss other songs. 

Thanks for the reply @bluezzbastardzz 

Not sure if it's the lagging issue - it has been happening consistently, and only when I let a playlist run. Manually selecting a new song or immediately going back and playing ten seconds of the missed song works.

The tracks weren't showing up in Deezer listening history when they didn't scrobble.

I didn't notice any of the tracks eventually being scrobbled. 

As an example, I had the self titled album by Hellyeah on shuffle.

Tracks 3, 5, and 10 in the play queue are missing from Deezer listening history. They were also missing on last.fm, until I played them again for 10 seconds and clicked on the next track. They're still missing on Deezer listening history.

This is consistently happening for every single play queue, although the exact track positions that are skipped are usually different.

@bluezzbastardzz Any advice would be appreciated, as I don't want to either skip 30% of my plays or constantly have to manually add them.

This worked perfectly for years until a couple of weeks ago. 

Did you actually listen to the missing songs, i.e. did you hear them play, or did you mute your phone to just scrobble the album? Sometimes Android phones can do weird things to save battery life like disabling background activity, so that might be a reason. The Deezer Android app seems to be buggy recently, another possible reason. Maybe the shuffle mode is a bad idea for album listening, what happens if you play the tracklist from top to bottom?

And as mentioned before, there are a lot of external Android scrobbling apps which you could use instead of the internal Deezer scrobbling option.

I did wonder that myself, especially since I've been listening to techno playlists with unfamiliar songs recently. Made an effort to pay attention, and it was definitely skipping tracks.

I tried another reinstall and fiddled with the smart cache size (decreased it a bit). Might have done the trick - last five albums have scrobbled fine.

None were shuffled though, but I think it was happening before on regular play too.

Will keep an eye on it, but hopefully that's it fixed.