[Galaxy S II Q&A, Help & Troubleshooting] graigchq:
Hi Everyone

Had my I9100G for about six months, bought here in Tanzania, working like a charm with Cyanogenmod 10.1, updated regularly, now on RC2 from this month.

I used to have an 8GB sd card, with all my music on it, and nothing else save the odd folders created by android itself. For my birthday I treated myself to a new Transcend 32GB Class 4 card, and set about formatting it and putting it in the phone, primary purpose to store more music.

So i copied over about 25GB of music using an SD adaptor on my PC, and then inserted, and obviously the media scanner takes a few minutes to sortit all out, so I left it there, then after about 20 minutes went into Winamp (my main music player) and found of the 4000 odd tracks, that 3800 of them had "Unknown Artist".

I promptly searched these forums and others for solutions or symptoms that might have caused this, and decided to go back and try again, perhaps they didn't copy properly. I have tried using the SD adaptor on my laptop, using USB mass storage from the phone, and also using MTP, all of which have this same horrible symptom: UNKNOWN ARTIST.

Lots of posts say that this is caused by wrong ID3 tags, but the funny thing is that all of the 7GB of music i had on there before is now on the new card, and those USED to show artist names, all of them come from my main mp3 collection on my laptop, and never had this before.

I created a folder on my laptop to put all the music onto my phone, and used mp3tag to read and re-write the tags to all 4000 songs, I checked, then put them on the SD card, then checked again that the tags were still there, but when I go into Winamp (or Apollo - same result) still shows many many unknown artists for mp3s that it has worked with before without issue.

Last night, I wiped, formatted, reflashed the ROM, didn't update any apps or restore my backups, just treated it like a brand new phone, and the same thing is happening, whether i put on 200 songs or 4000 songs. It has now read the tag details for some of them, like Track 1 of lots of albums, but the other 10-15 tracks of each album have no artist. They do however show album artwork and song and album names, but no artist or genre.

What makes it worse, is that if I put my old 8GB card back in, it does the same thign to the music that USED to work fine!!!???!!!

Does anybody have any idea what could be causing this?? I don't think its the SD card, which I have tried formatted by the phone in CWM (which makes it unreadable in android) formatting FAT32 on the computer with allocation blocks of 16, 32 and 64kb, none of which make any difference. The way it is now is 16kb allocation blocks (default fo rthe card) and long formatted in windows (not the quick format - it took about 30 minutes to complete).

I shouldn't lose sleep over this, but its driving me crazy, as there are songs and albums that it used to recognise, and that the tags are there and valid in IDv3v1 and IDv3v2.3, nothign is mising, but the phone does not read them properly.

Also now it shows a different number of total tracks on each reboot, sometimes 3800 sometimes 3700 sometimes 3900....

Anybody know what else I can try???