First chose your tracks
then if they are in mp3 format use for example
this freeware tool : Free Mp3 Wma Converter V1.91
and restore them first to wav format.
Then with a version of wavelab or an Audio editor of your choice
you will convert them again to :
Extention : .wav
Audio format : mp3
Channels : (the same as source)
Sample Rate : 44100Hz
Encoding : LameEnc / 192 Kbps, 44100Hz Stereo
Here's a batch for the :Grossdeutscher_Rundfunk
http://www.zg52.com/zips/Grossdeutscher_Rundfunk.rar
and you extract it here :
Ubisoft\IL-2 Sturmovik 1946\samples\Music\Radio\Grossdeutscher_Rundfunk
the directions i give are precise & work fine -
the format used by 1C, for example pilot chatter has the following format :
General
Complete name : D:\GAMES\Ubisoft\IL-2 Sturmovik 1946\samples\Speech\DE\Actor4\Warning_Traffic_is_o n_the_runway_Go_round_repeat_go_round.wav
Format : Wave
File size : 13.3 KiB
Duration : 5s 433ms
Overall bit rate : 20.0 Kbps
Audio
ID : 0
Format : MPEG Audio
Format version : Version 2.5
Format profile : Layer 3
Codec ID : 55
Codec ID/Hint : MP3
Duration : 5s 433ms
Bit rate mode : Variable
Bit rate : 20.0 Kbps
Channel(s) : 1 channel
Sampling rate : 11.025 KHz
Stream size : 13.2 KiB (99%)
however for music there are small diferences :
General
Complete name : D:\GAMES\Ubisoft\IL-2 Sturmovik 1946\samples\Music\Menu\de.wav
Format : Wave
File size : 3.20 MiB
Duration : 2mn 19s
Overall bit rate : 193 Kbps
Audio
ID : 0
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 3
Mode : Joint stereo
Codec ID : 55
Codec ID/Hint : MP3
Duration : 2mn 19s
Bit rate mode : Constant
Bit rate : 192 Kbps
Channel(s) : 2 channels
Sampling rate : 44.1 KHz
Stream size : 3.20 MiB (100%)
So .. as you can see .. if you stick to the basic instructions i give you will be ok ...
instead of Wavelab you can also use a free version of Cool Edit!