Transcription FAQ: Good Audio vs. Bad Audio

Setting The Record Straight

Think about a time when you have been talking on the phone and the connection begins to cut out, or you are talking to someone at an event and trying to yell over the background noise, or the volume of their voice is too low? It is difficult to hear what is said and often you have to end the call.

Now, take that same experience and think about how hard it would be to type out what they were saying with correct grammar and 99% accuracy—that is no easy feat even when the audio is pristine.

The guys over at fixing your video produced an excellent video that goes in-depth on the ways to make your audio better. I have outlined the key points below for easy reference, but I highly recommend watching it if you have the time.

Key Points

Can’t you just clean up the audio?

“Well, cleaning up audio is like trying to take salt out of your dinner, once it’s part of the food it’s gonna be hard to take it back out. You might be able to pick out an obvious grain or two but other than that your best bet is usually to start from scratch.”

That is a great analogy because like salt in your food, noise becomes engrained with your file and is almost impossible to remove.

Good audio quality is essential to your project’s success because humans are mostly visual, but sound is integral when it comes to communication. Make sure you take the following measures to record high-quality audio so you do not end up stuck with something you can’t fix in post.

“cleaning up audio is like trying to take salt out of your dinner, once it’s part of the food it’s gonna be really hard to take it back out.”

Cleaning Audio in Audacity

We have written about how to do this as well, but they offer a few unique solutions.

  1. Use the “Effects: Noise Removal” plugin and then “Get Noise Profile.” This step tells Audacity to remove this type of noise from the file. Note: This method can eliminate a lot of the good audio too.
  2. Soundsoak 3: This method uses a similar but a more advanced “Learn noise” method to reduce the aberrant noise.
  3. Use an EQ plugin to bring up the low end after noise removal.

How to keep out background noise in the first place

MicrophonesScribie Microphone

  1. Since they are focused on video, they advocate for lavalier microphones, but if you are not making a video, then we have put together a list of recommended microphones.
  2. They also touch on some other types of recorders such as the Zoom H4N and the Zoom H2 as well as your phone.
  3.  “As a rule of thumb: the closer the mic, the cleaner the sound.”

Avoid The Noise

  1. Some background noises simply can’t be defeated, and you need to move away from the sound.
  2. Microphones are a lot more sensitive than our ears!
  3. The software is only good at removing basic noise.

Always Wear Headphones

Scribie Audio HeadphonesThe only way to know that you are recording clean audio is to monitor it while it is recording. This tip may seem a bit much, but I assure you that you will not regret it. If you are in an interview and are worried about the headphones being distracting to whomever you are recording, then you might try using only one earbud. You can monitor the audio for any spikes or background noise while not making the interview awkward by wearing enormous headphones.

Thanks to fixingyourvideo for creating this excellent resource on good vs. bad audio.


Skype Desktop API Disabled?

The CallGraph Skype recorder is built on the Skype Desktop API. Some parts of the API was deprecated by Microsoft last year. The announcement can be found at the following link.

Fortunately CallGraph did not use those APIs and was still working. With the Skype update however, it seems that some more APIs have been removed from Skype. We have received multiple bug reports that CallGraph has stopped working after this update. CallGraph does not seem to receive any data from Skype and therefore the other side of the call does not get recorded. But there has been no update from Microsoft regarding this.

The best advice we can give right now is to try out the other Skype recorders listed on the Skype Website. Some of them are free and still available. If the API has been deprecated, then none of the Skype recorders will work.

In the meantime, if you are facing issues with CallGraph, please enable logging, record a test call and send it to We will keep monitoring the situation and update whenever we have more information.

CallGraph: Stereo vs Mono Recording

CallGraph Skype Recorder records by default in stereo mode which means that your voice and other participant(s) voice are on different tracks in the file. While playing back you will hear your voice on one side of the speaker while your caller/callee’s voice on the other side. To force CallGraph to record in a single track change the channels to mono from Configuration -> Recording tab (how-to). This change will affect all subsequent calls recorded with CallGraph. For older one’s, you can convert them to mono using an audio editor (eg. Audacity).

The stereo mode is useful if you’re recording podcasts since you can edit each track separately. Having voices on separate track makes it easier by an order of magnitude. It also helps with the transcription of audio file and we recommend that you record in stereo mode if you plan to get it transcribed.

Sometimes due to misconfiguration of the PC’s playback settings, only one track is audible during playback and it appears that CallGraph is recording only one side of the call, even though Skype connection has been authorized. A quick fix is to set the recording mode to mono.

Invalid Certificate Issue Resolved

Due to an incorrectly configured SSL certificate on our server browsers were showing an security warning whenever any secure pages on were accessed. We have corrected the configuration now and the security warning should go away. If you had faced the issue then please try now. Technical details follow.

The problem was that the intermediate certificates supplied by our CA was not specified. When we moved our domain to we also changed over from Apache to Nginx. In Apache the intermediate certificates where specified by the SSLCertificateChainFile directive. But Nginx does not have a corresponding directive. In Nginx the intermediate certificates have to combined into the server certificate PEM file. Once we did that, the security warning went away.

The odd part was we had run into the same error when we did the domain transition and were testing it out. But that error went away when we did force reloads of the page. So we thought it was an intermittent error which would go away eventually. But it did not and one of our users complained about it yesterday. In the end it turned out to be a simple fix.

One Sided Recording

If you run into the situation where you recorded a Skype call with CallGraph but you can hear only one side of the conversation when you play it back, then there are two things you can do.

  1. Check if CallGraph has been authorized to connect to Skype. Without Skype authorization CallGraph cannot access the voice data from the Skype call and therefore cannot record the other side of the conversation. Skype authorization process can be sometimes tricky. If you face any issues then check the post on troubleshooting tips.
  2. If authorization has been done, then try setting the recording mode to mono from configuration -> general tab and recording another test call. CallGraph records by default in stereo mode where your once and everyone else’ voice is encoded on different tracks. Unfortunately some PC’s are not configured correctly to play such files and you can hear only one track during playback. In mono mode both channels are mixed into a single track.

Once CallGraph has been authorized to connect to  Skype it should be able to record both sides of the conversation just fine.

Skype Unable to Respond

If you get the message “Another application (CallGraph.exe) is attempting to access Skype, but we are unable to respond” from Skype, here are few things you can do to resolve this issue.

  1. Make a call to Skype Test Call Service (echo123) or any other contact. This will force Skype to check it’s database of whitelist’ed plugins and respond to CallGraph thereafter.
  2. Restart both Skype and CallGraph several times. To exit CallGraph, click on the CallGraph system tray icon and choose exit from the popup menu. Same for Skype.
  3. Try starting CallGraph after 15-20 minutes of starting Skype. This will allow Skype to settle down a bit and have more time to respond to CallGraph.
  4. Ensure that both Skype and CallGraph are running as non-admin. Both Skype and CallGraph do not require admin permissions to run.
  5. Check if your Antivirus or Firewall is blocking the communication between Skype and CallGraph. Try adding exceptions for both Skype and CallGraph.
  6. Try re-installing both Skype and CallGraph.
  7. Try restarting your PC.

For 64 bit machines, please try the following

  1. Uninstall CallGraph completely.
  2. Download and install the vcredist_x64.exe from the Microsoft website.
  3. Install CallGraph again.

Click here for step-by-step instructions on how to authorize CallGraph to connect to Skype.

From our testing what we have found is Skype is usually able to respond back after a few tries. So restarting CallGraph a few times works. If nothing works then enable logging in CallGraph (configuration -> general tab), restart CallGraph, start recording and stop it after 5 seconds and send the log file to

Known Issues v1.3.0.0

Here’s the list of know issues for CallGraph Skype Recorder version

  • If back to back calls are made/received from Skype then the second call may not be correctly recorded. The recording file for the second call does not contain the audio the second call, but the first call. This happens only in few cases. To prevent this from happening please ensure that there is at least 30 second gap between the end of the first call and start of the second.

We have been chasing this issue but have not been able to reproduce it at our end. If you have faced it, then it will be a big help if you can enable logging from configuration -> general tab, reproduce the issue and send us the log file. Thanks!

We will keep on adding to this list as we discover issues. Please report any issues you face with CallGraph Skype recorder to Thanks in advance.

Known Issues v1.2.1.1

  • On some setups starting the recording mutes the callers voices. To prevent this turn off the Near End EC option from configuration -> advanced tab.
  • Exiting Call Graph just after the recording is finished or in between the recording might cause a crash. The files are however saved and the call is restored.
  • When playing back voicemails Call Graph gives a false notification that the call is being recorded.
  • MP3 conversion of files which have apostrophes in their name fails. For a workaround remove the apostrophe from the name.

We’ll be adding to this as we discover more. Please let us know if you find one.


All the above issues have been resolved in version Please upgrade now.