There is a very easy way to record our own announcement. In windows system, there is a tool "sound recorder" can do that. Please click "start->Run ..." and enter "sndrec32.exe" to run it. For windows Vista/Windows 7, the default 'sound recorder' application is changed and we cannot use it to record WAV files. Please click here to get 'sndrec32.exe'.
Press button 1 to begin record your announcement and press button 2 to stop recording. Then, please click menu "File->Save as ..." to save your announcement. In the "Save as ..." window, please click "Change ..." button to change WAV format.
In the popup "Sound selection" window, please select "CCITT A-Law" format, and select "8KHZ, 8Bit, 7kb/sec" attributes.
Then, we can save this new audio file into 'custAnn' subdirectory which is in the AppData directory. Then we MUST restart miniSIPServer to reload this audio file.
By the way, if we have some others audio files but not in such audio format, we can also use "sound recorder" tool to convert it to above format and attributes.
Please refer to manual document for more details about miniSIPServer audio ID.