The recent upgrade the the GoPro Firmware has disabled the least compression rate of the GoPro recording on certain cards. Those that don't make the throughput that GoPro wanted.
One of those cards was the Sandisk Extreme cards because Hero was constantly getting complaints about them not performing properly.
At the camera's best, it will record at over 45mbs, but thanks to the new firmware, only on cards that are up to specs. They list 4 cards on their web site that are up to the task, but there are others that are also good enough. On cards where tje performance wasn't up to snuff, they throttle it back to just 35mbs.
Now, I use a cheap ADATA card. I have 2 of them, and they both read and write at the highest rate. I've even recorded as much as 30 minutes at 720p120 in Protune and have been fine.
The difference in price between the card I use - typically $24.95 and the Approved Lexar and Samsung cards - $99.95 is huge, so I would not necessarily buy the recommended card. I just, at this point would not choose Sandisk. There is a war brewing there for sure.
Lastly, you can check the write speed by left mouse clicking on your file and looking under properties. It will say there.
You should also know there may be no perceptible difference between the two different write speeds. I can't test it as my card writes at the max. Perhaps someone else can do it if they have two different cards.
D
