Strange folders during sync of MMW and MMA

[Ticktack]

Hi,

I am currently in the process of syncing my music library from MMW to MMA on my smartphone by WiFi. Since this takes a rather long time, I already canceled the process to resume it later on.

Now in the target directory on my smartphone I got some strange folders besides the ones that are supposed to be there. The names of these folders consist of a long row of numbers and all start with a dot and end with an underscore and a zero, e.g. like this:
.8014755057549201662_0

Most of these folders are empty, some contain a few MP3 files that are also contained in the properly named folders.

Can I delete these folders? Did they occur because I canceled the sync process?

[Ticktack]

Update: Seems like this was a temporary problem associated with the unfinished or canceled sync. Now after the sync has been finished these strange folders are gone.