Unsupported wave format

Mar 18 at 4:00 AM
I am using nAudio for wasapi loopback capture in a c# application (my first!), so a big thank you for Naudio!

I have handed the application to a few friends, to test and it seems to run fine for them all - everyone is win 7 .net4.5, one however is getting the following error and I am unable to recreate it and since he is in another country I don't have access to the comp directly to debug easily.

Has anyone seen this issue before/have an idea what the cause could be off hand, or can give me a pointer as to how to get a better idea of what's causing it?
System.ArgumentException: Unsupported Wave Format
   at NAudio.CoreAudioApi.WasapiCapture.InitializeCaptureDevice()
   at NAudio.CoreAudioApi.WasapiCapture.StartRecording()
I am initialising similar to the demo:
waveIn = new WasapiLoopbackCapture();
writer = new WaveFileWriter(Path.Combine(outputFolder, outputFilename), waveIn.WaveFormat);
Many Thanks in advance,
Mar 18 at 9:21 AM
do you get the error recording, or trying to replay the file?
Mar 18 at 11:25 AM
Thanks for the reply, the error comes when trying to record, interestingly the only difference in setup I have found so far is that he is running win 7 professional.
Mar 18 at 12:22 PM
I've experienced this when the format listed on the advanced tab of the microphone properties doesn't match the wave format in the code
Mar 18 at 12:28 PM
WasapiLoopbackCapture will usually be 44.1kHz or 48kHz, stereo, and 32 bit floating point. What might be catching you out is that WASAPI likes to use WAVEFORMATEXTENSIBLE in preference to a regular PCM/IEEE float WAVEFORMATEX

What actually is the contents of waveIn.WaveFormat?
Mar 18 at 3:09 PM
Edited Mar 18 at 3:27 PM
@erminh Will double check that when I can tonight, thank you.

@Mark I am not actually setting it directly, would make sense that this is the issue - am curious as to why it would work for others in this case though. Checking the contents on my machine it is: IeeeFloat, so looks as though I do need to change that to WAVEFORMATEXTENSIBLE. Sorry for my super noobieness, how and when should I set that in the above code?
Mar 18 at 3:11 PM
normally you should not be setting it at all, which is why I am interested in finding out what it actually is
Mar 18 at 3:41 PM
Edited Mar 18 at 4:01 PM
Sorry edited before I had refreshed to check answers,

Checking the contents on my machine it is: IeeeFloat, so looks as though I do need to change that to WAVEFORMATEXTENSIBLE. Will try and find out from my friend what it contains on his machine and post back.
Mar 19 at 3:17 PM
Just to update, in case anyone else has this problem. The issue was an out dated Realtek Audio Driver. Updating it has fixed the issue.

Big thanks for the help though!
Mar 19 at 3:19 PM
great, thanks for sharing what the problem is. I've had issues with Realtek drivers in the past