With Converter App, you can convert AC3 files into many other formats:
AC3 to MP3 | AC3 to TEXT | AC3 to M4A | AC3 to FLAC | AC3 to AAC | AC3 to WAV
→ All AC3 Converters
If you want to keep working with your final M4A, try:
M4A to MP3 | M4A to WAV | M4A to TXT | M4A to DOCX | M4A to PDF | M4A to FLAC | M4A to AAC | M4A to OGG
→ All M4A Converters