This affects me on both self-compiled and repository binary:
- MOV (Canon DSLR) and WAV (ZOOM Audio Recorder) files throw errors and do not generate audio thumbnails. The issue persists even after the WAV file is converted to MP3 (Using Audacity) and the MOV is converted to an MPEG4 M4V (Using Handbrake).

- MP4 and MP3 formats DO generate waveform thumbnails as expected, provided that they're not conversions of the previously mentioned files. However, when a working MP3 file is converted to WAV, it can no longer generate thumbnails.

Reproducible: Always

Steps to Reproduce:
1. Import a MOV from a Canon DSLR or WAV from a ZOOM Audio Recorder

Actual Results:  
Program continued working without waveform thumbnails for the project.

Expected Results:  
Generated waveform thumbnails.

mlt_repository_init: failed to dlopen /home/benjamin/Dev/kdenlive/lib/mlt/libmltopengl.so
  (libmovit.so.2: cannot open shared object file: No such file or directory)
Removing cache at "/home/benjamin/.cache/kdenlive-thumbs.kcache"
OpenGL vendor:  "NVIDIA Corporation"
OpenGL renderer:  "GeForce GTX 660 Ti/PCIe/SSE2"
OpenGL ARG_SYNC:  true
OpenGL OpenGLES:  false
OpenGL vendor:  "NVIDIA Corporation"
OpenGL renderer:  "GeForce GTX 660 Ti/PCIe/SSE2"
OpenGL ARG_SYNC:  true
OpenGL OpenGLES:  false
[swscaler @ 0x7fffad3509c0] Warning: data is not aligned! This can lead to a speedloss
"Creating audio thumbnails (1/1)"
"Error reading audio thumbnail"
"Creating audio thumbnails (1/1)"
"Error reading audio thumbnail"
"Error reading audio thumbnail"
"Error reading audio thumbnail"
 / / / / /WARNING, VIDEO CONTEXT IS NULL!!!!!!!!!!!!!!
"Creating audio thumbnails (1/1)"
"Error reading audio thumbnail"
/// READY TO CUT AT:  1071  /  1071 , duration:  476
// chking moved clip at:  1071
// chking moved clip at:  1071
QPainter::begin: Paint device returned engine == 0, type: 3
QPainter::setOpacity: Painter not active
QPainter::setOpacity: Painter not active
QPainter::end: Painter not active, aborted
Adjusting effect to duraion
Adjusting effect to duraion
Adjusting effect to duraion
Adjusting effect to duraion
Adjusting effect to duraion
/// READY TO CUT AT:  305  /  305 , duration:  237
// chking moved clip at:  305
// chking moved clip at:  305
Adjusting effect to duraion
Adjusting effect to duraion
1462680744293	addons.productaddons	ERROR	Request failed certificate checks: [Exception... "SSL is required and URI scheme is not https."  nsresult: "0x8000ffff (NS_ERROR_UNEXPECTED)"  location: "JS frame :: resource://gre/modules/CertUtils.jsm :: checkCert :: line 145"  data: no]

(process:9391): GLib-CRITICAL **: g_path_get_basename: assertion 'file_name != NULL' failed
"Creating audio thumbnails (1/1)"
/// READY TO CUT AT:  606  /  606 , duration:  211
// chking moved clip at:  606
// chking moved clip at:  606
[mp3 @ 0x30b6760] Estimating duration from bitrate, this may be inaccurate
[mp3 @ 0x3526040] Estimating duration from bitrate, this may be inaccurate
[mp3 @ 0x3c6e9e0] Estimating duration from bitrate, this may be inaccurate
[mp3 @ 0x34d86a0] Estimating duration from bitrate, this may be inaccurate
 / / / / /WARNING, VIDEO CONTEXT IS NULL!!!!!!!!!!!!!!
"Creating audio thumbnails (1/1)"
QPainter::begin: Paint device returned engine == 0, type: 3
QPainter::setOpacity: Painter not active
QPainter::setOpacity: Painter not active
QPainter::end: Painter not active, aborted
[mp3 @ 0x7ffdf3ed9960] Estimating duration from bitrate, this may be inaccurate
[mp3 @ 0x7fff8813db20] Estimating duration from bitrate, this may be inaccurate
 / / / / /WARNING, VIDEO CONTEXT IS NULL!!!!!!!!!!!!!!
"Creating audio thumbnails (1/1)"
"Error reading audio thumbnail"
1462681524145	addons.productaddons	ERROR	Request failed certificate checks: [Exception... "SSL is required and URI scheme is not https."  nsresult: "0x8000ffff (NS_ERROR_UNEXPECTED)"  location: "JS frame :: resource://gre/modules/CertUtils.jsm :: checkCert :: line 145"  data: no]
1462681525461	addons.update-checker	WARN	Update manifest for {972ce4c6-7e08-4474-a285-3208198ce6fd} did not contain an updates property
 / / / / /WARNING, VIDEO CONTEXT IS NULL!!!!!!!!!!!!!!
"Creating audio thumbnails (1/1)"
"Error reading audio thumbnail"
QPainter::begin: Paint device returned engine == 0, type: 3
QPainter::setOpacity: Painter not active
QPainter::setOpacity: Painter not active
QPainter::end: Painter not active, aborted
 / / / / /WARNING, VIDEO CONTEXT IS NULL!!!!!!!!!!!!!!
"Creating audio thumbnails (1/1)"
"Error reading audio thumbnail"
"Creating audio thumbnails (1/1)"
 / / / / /WARNING, VIDEO CONTEXT IS NULL!!!!!!!!!!!!!!
"Creating audio thumbnails (1/1)"
"Error reading audio thumbnail"
*** Exited normally ***