Updated

Google Music's new scan and match feature seems to have hit a sour note. Introduced just before the holidays, scan and match is designed to cut back on the tediousness of uploading your music en masse to the cloud. Music now scans the content of your library and if you own any songs that are available via Google's own digital catalog, the company simply makes the tracks available to you—no uploading required.

If only it were that easy. Droid Life reports that some users are complaining that Google Music's match feature is swapping out songs with explicit lyrics for scrubbed-clean, non-explicit versions, while The Verge reports hearing tales of the converse: Some clean songs are being replaced by their R-rated original version.

The issue is exacerbated by the fact that Google will no longer let you manually upload songs that it already stores on its servers. If Google can match the songs in your library, you must rely on the company's version. Amazon and Apple's scan and match offerings for their competing services carry the same requirement.

Speaking of Apple's scan and match functionality, Google Music's growing pains may seem like old news to veteran iTunes users; that service suffered from similar explicit lyric-swapping woes when iTunes Match was introduced.