If you want to try my finished file you can download it here: winemp3.acm.so (x86 only)
Place it in /usr/lib/wine/ (x86) or /usr/lib32/wine/ (x64).

Or if you need to do things a tad more automatic you can try this script which will do everything automatically for the ones of you on x86: winefix.sh

For those of you who want the technical details: continue reading

You should try and skip step 3 if possible, but if Spotify just hangs and max out your CPU you should do step 3.

You can also use an hex editor to change WINE-MPEG3 to LAME-MPEG3 in /usr/lib/wine/winemp3.acm.so to try before doing the, for me, crucial step number three.

Step 1: Download the wine source code.
Step 2: run configure to create the appropriate Makefiles
Step 3: edit dlls/winemp3.acm/mpgl3.c and change the following:

if (dpos > *ndst) break;
} while (ret != MPG123_ERR && ret != MPG123_NEED_MORE);
*ndst = dpos;


To this:


if (dpos >= *ndst) break;
} while (ret != MPG123_ERR && ret != MPG123_NEED_MORE);
*ndst = dpos;

Step4: Change the following:

add->cFilterTags = 0;
add->hicon = NULL;
MultiByteToWideChar( CP_ACP, 0, "WINE-MPEG3", -1,
add->szShortName, sizeof(add->szShortName)/sizeof(WCHAR) );


To this:

add->cFilterTags = 0;
add->hicon = NULL;
MultiByteToWideChar( CP_ACP, 0, "EFO", -1,
add->szShortName, sizeof(add->szShortName)/sizeof(WCHAR) );


Step 5: Run make to compile the new codec.
Step 6: copy the codec to /usr/lib/wine/ (ubuntu atleast)
Step 7: Run Spotify and enjoy.

This worked for me, but it is not recommended as i changed some code in the MP3 library in Wine.
If you use Wine with other programs which utilizes the mpeg3 library they might break.

UPDATE 1: It seems like my hack will give some problems with automatic changing of songs. The codec does not understand that the song is finished, and will just generate noise.

UPDATE 2: Ok, new fix. This time it does infact end where it should, and continues to the next track. Step 3 is updated. Same with the binary file, and scripts.

UPDATE 3: Moved around some text in this post.