Convert Shoretel WAV Files: Fast, Reliable Shoretel WAV Converter

Troubleshooting Shoretel WAV Conversion Errors and FixesShoreTel (now part of Mitel) phone systems often record call audio in WAV files that use specific codecs or container formats. Converting these Shoretel WAV files to more common formats (like standard PCM WAV, MP3, or AAC) can sometimes produce errors—unplayable files, wrong sample rates, or corrupted audio. This article walks through common conversion problems, diagnostic steps, and reliable fixes so you can recover usable audio and build a more resilient conversion process.

1. Understand Shoretel WAV characteristics

Before troubleshooting, it helps to know what makes Shoretel WAV files different:

• Proprietary codec/container: Some ShoreTel systems use nonstandard WAV headers or compressed codecs (G.711 μ-law/A-law, G.722, etc.) inside a WAV container.
• Channel layout: Recordings may be mono, stereo (separate channels for each party), or interleaved formats.
• Sample rate & bit depth variations: Common sample rates include 8000 Hz for telephony codecs or 16000 Hz for wideband codecs; bit depth is often 8-bit or 16-bit.
• Filename/metadata conventions: ShoreTel might add metadata or custom headers that standard players ignore or choke on.

Knowing these helps choose the right tools and conversion parameters.

2. Common conversion errors and what they mean

• “File not recognized” or “Unsupported format”: The converter doesn’t understand the WAV header or embedded codec.
• Distorted audio (garbled, high-pitched, or low rumble): Likely wrong sample rate, bit depth, or decoding the wrong codec (e.g., treating μ-law as PCM).
• Silent or one-sided audio: Channel mapping issues or missing codec support for interleaved channels.
• Partial conversion or truncated files: Corrupt headers, incorrect file length metadata, or abrupt file termination.
• Crashes or freezes in conversion software: Memory issues with large batch files or malformed headers causing parser errors.

3. Diagnostic checklist — how to inspect a problematic file

1. Make a copy of the original file. Work on copies only.
2. Check file details with media inspection tools:
   • Use ffprobe (from FFmpeg) or MediaInfo to inspect codec, sample rate, channels, and container. Example: ffprobe -v error -show_format -show_streams file.wav
3. Play the file in a robust player (VLC or Foobar2000) that supports many codecs; note error messages.
4. Inspect header bytes with a hex editor if you suspect a nonstandard header. Compare with a known-good ShoreTel WAV from the same system.
5. Try to open the file with ShoreTel/Mitel software (if available) which may correctly parse proprietary headers.

4. Fixes by error type

• Unsupported format / unrecognized file
  • Use FFmpeg which supports many telephony codecs. Try forcing codec options:

    
    ffmpeg -f u8 -ar 8000 -ac 1 -i input.wav -acodec pcm_s16le output.wav 

    Replace -f u8 with -f mulaw or -f alaw if appropriate, and adjust -ar to 8000 or 16000 accordingly.

  • If header is proprietary, strip the header using a hex editor or write a small script to remove the extra bytes, then rewrap the raw audio into a standard WAV:

    
    ffmpeg -f s16le -ar 16000 -ac 1 -i raw_audio.bin output.wav 

• Distorted / pitched / noisy audio
  • Confirm sample rate and bit depth with ffprobe/MediaInfo. If the file was recorded at 8000 Hz but treated as 44100 Hz, resample:

    
    ffmpeg -i input.wav -ar 8000 -acodec pcm_s16le output_8k.wav 

  • Try decoding with μ-law or A-law:

    
    ffmpeg -f mulaw -ar 8000 -ac 1 -i input.wav -ar 8000 output.wav 

• Silent or one-sided audio
  • Inspect channel layout. If channels are interleaved with each party on separate channels, downmix to mono or split channels:
    • Downmix to mono:

      
      ffmpeg -i input.wav -ac 1 output_mono.wav 

    • Extract channel 0 or 1:

      
      ffmpeg -i input.wav -map_channel 0.0.0 left.wav ffmpeg -i input.wav -map_channel 0.0.1 right.wav 

• Truncated or partial files
  • If the header states a larger data size than the file contains, tools may choke. Create a corrected header using sox or ffmpeg by re-encoding:

    
    ffmpeg -err_detect ignore_err -i input.wav -c:a pcm_s16le fixed.wav 

  • Use data-recovery tools to concatenate segments if the recording system split files. Look for consistent timestamps/filenames.
• Conversion software crashes
  • Break large batches into smaller groups. Use command-line FFmpeg (more stable for automation) rather than GUI apps. Monitor memory and disk I/O.

5. Recommended conversion workflow (robust and automatable)

1. Inventory: Collect files and log filenames, sizes, and timestamps.
2. Inspect: Run ffprobe/MediaInfo to record codec, sample rate, channels into a CSV.
   Example command:

   
   ffprobe -v quiet -print_format json -show_format -show_streams file.wav > file.json 

3. Branch logic script:
   • If codec is mulaw/alaw → decode with appropriate -f.
   • If sample rate ≠ desired sample rate → resample with -ar.
   • If channels >1 and you need mono → downmix.
4. Convert with FFmpeg using deterministic parameters:

   
   ffmpeg -hide_banner -loglevel error -i input.wav -ac 1 -ar 16000 -c:a pcm_s16le output_converted.wav 

5. Validate: Play a brief segment or run a checksum comparison against expectations (duration, rms level).
6. Archive originals and converted files with metadata CSV for traceability.

6. Tools and scripts that help

• FFmpeg/ffprobe — main workhorse for decoding, rewrapping, and batch processing.
• SoX — useful for resampling and repairing WAV headers.
• MediaInfo — quick GUI inspection of codecs/streams.
• Hex editor (HxD, Bless) — for header inspection and byte-level fixes.
• Python scripts using pydub or wave + numpy — for custom fixes (stripping headers, channel manipulation). Example snippet for rewrapping raw data:

  
  from pydub import AudioSegment raw = AudioSegment.from_file("raw_audio.bin", format="raw", frame_rate=8000, sample_width=2, channels=1) raw.export("fixed.wav", format="wav") 

7. Preventive measures and best practices

• Configure ShoreTel/Mitel recording to use standard codecs (G.711 μ-law or 16-bit PCM) and consistent sample rates if possible.
• Keep a known-good WAV sample from the system as a reference for future conversions.
• Include logging in conversion scripts to capture failures and file metadata for debugging later.
• Schedule periodic validation: randomly sample converted files to ensure audio quality remains acceptable after updates.
• Avoid editing files in-place; always keep original recordings archived.

8. When to involve vendor support or forensic recovery

• If multiple files from the system show the same proprietary or encrypted header that standard tools can’t decode, contact Mitel (ShoreTel) support for format docs or an export utility.
• For legally critical recordings that are corrupted, consider a digital audio forensic specialist who can attempt header reconstruction and data recovery.

9. Quick reference FFmpeg commands

• Detect file info:

  
  ffprobe -v error -show_format -show_streams file.wav 

• Force decode μ-law to PCM:

  
  ffmpeg -f mulaw -ar 8000 -ac 1 -i input.wav -c:a pcm_s16le output.wav 

• Resample and downmix:

  
  ffmpeg -i input.wav -ar 16000 -ac 1 -c:a pcm_s16le output_resampled.wav 

• Extract left/right channel:

  
  ffmpeg -i input.wav -map_channel 0.0.0 left.wav ffmpeg -i input.wav -map_channel 0.0.1 right.wav 

If you want, I can: 1) analyze a specific Shoretel WAV file (tell me how you can upload it), 2) generate a ready-to-run batch FFmpeg script tailored to your codec/sample-rate needs, or 3) produce a short troubleshooting checklist card you can print.