I have set up call recording with “ulaw” format, and recordings do have a .ulaw extension, but I can’t play them back, with ulaw settings on CoolEdit I can hear the audio play way too fast, I can’t make out the words.
What’s the proper way to play these back? What is their REAL format, since it’s obviously not vanilla ulaw?
Generally, is there a utility that can identify the format of an audio file?
It is raw G.711 mu-law with no meta data. If Cool edit is playing them back too fast, it is broken, as mu-law is only ever used at 8kHZ mono, in practice.
I recorded with ulaw setting and it played back too fast, yesterday I switched to “wav” (not “WAV”) and it STILL plays back too fast, I have seen asterisk-developer postings identifying it as a bug, something about problematic recording with BRI cards, there’s no question about it, it’s not working right. Plus some parts of the audio play back fine, so the problem is 100% within Asterisk and not CoolEdit or any other player I have tried.
As you have dahdi, I would suggest trying the various dahdi show options. The source for non-dahdi purposes is set in the compile time options, using make menuconfig.
It’s only a guess though. I’ve never experienced problems with sample rates on recordings.