Before to panic I have to say that the audio test you can hear on top has been boosted to display the issue. In any normal recording condition you will not notice the issue at all! So this is just for “audio-peepers”.
Suggestionofmotion posted that video on top to show the background audio issue on the GH4:
It’s common knowledge that camera preamps are not the highest quality to begin with. The best practice is to set the in-camera audio gain as low as possible to keep the camera from introducing noise.
Now instead of just noise, we also have a buzz to contend with in the GH4. Just like noise, the buzz is always there regardless of gain level.
At the same time, like noise, if you set the gain as low as possible and feed the camera a strong audio signal, the buzz is buried pretty well.
The good news is 1) In no real word recording condition you will notice that and 2) Panasonic is already working to fix this (Source: Facebook). So unlike Suggestionofmotion I do not see that as a serious issue. TheDingo at DVXuserforum answered to that video test:
When I first heard about this audio buzz issue I was a bit worried about the audio quality of the GH4, but the more I hear about it, I am becoming convinced this is people listening to the actual noise-floor of the camera, which is something that would NEVER happen if you have all your audio ducks in a row.
So don’t worry guys!
North American preorders, shipping date and price:
GH4 camera at Amazon, Adorama, BHphoto, Ritz Camera and Panasonic. Price: $1,698. In Canada at Vistek.
GH4 camera with interface unit at Adorama and BHphoto. Price: $3,298
Interface unit only at Amazon, Adorama, BHphoto and Panasonic. Price: $1,998
Europen preorders, shipping date and price:
Germany: Wexcameras, Marcotec-shop.de.
UK at Wexphotographic, CameraWorld, UKdigital, CVP, TipTop.
Holland at Fotohanskeuzekamp.
Belgium at Fotokonijnenberg.
Norway at Fotovideo.
Sweden at Cyberphoto, Skandinavianphoto.
Finland at Telefoto, Topshot, Verkkoauppa.
France at Photocineshop.
Spain: Fotoboom.
Asian preorders, shipping date and price:
Digitalrev and Digidirect Australia.
4K cards
Kingston 16-32-64 GB SDHC UHS-I Speed Class 3 at Amazon (Click here), Adorama (Click here) and BHphoto (Click here).
Sandisk 16-32-64 GB Extreme PRO SDXC UHS-II Memory Card at Amazon (Click here), Adorama (Click here) and BHphoto (Click here).
Transcend 64-128 GB High Speed 10 UHS-3 at Amazon (Click here) and BHphoto (Click here).
Panasonic 16-32-64 GB SDHC-UHS-I U3 Card (90MB/s) at Adorama (Click here) and BHphoto (Click here).