Speed test your MicroSD Card!
A majority of camera recording issues are down to a slow memory card.
A friend of mine performed a speed test on his MicroSD card, which he purchased from a local store, and found that it was most likely a fake, or faulty, card since the actual speed was no way near the manufacturer quoted speed.
Hence I've just tested my Sandisk Extreme 32GB cards and am getting the proper speeds (90MB/s Read, 50MB/s write), so I can be pretty sure they are not fakes!!
If you are a few MB/s off from the manufacturer quoted speeds you are fine - thats completely normal.
If you are way off, then there's a problem!
NOTE: I purchase my cards from Amazon. If buying from Amazon make sure its from Amazon direct - NOT a third party reseller on Amazon!
There are various free speed testing programs you can use - such as BlackMagic Disk Speed Test.