I'm going to give it a try since I want my internal card option back.
The new firmware
FW VER: 20130911 for DVRs Procam CX4 version 2.0 and above
with built-in memory of 8 GB.
Changes:
1) storage format. MOV instead. TS
2) A higher bit rate recording
3) Optimized algorithm for processing and packaging of video
2) Increased stability of the device
3) Improved quality video at night and during daytime
4) Improved audio recording
lies on the site procam.ru
add file 1 minute 140MBytes, variable bit rate up to 19Mb
removed the inscription Procam.
I only skimmed over these translated forum posts in the past, after reading a bit more, there is a LOT of interesting in depth information here:
http://translate.google.com/translate?hl=en&sl=ru&u=http://videoregforum.ru/threads/procam-cx4.480/page-12&prev=/search?q=20130823+firmware+procam&biw=1355&bih=803
Have a read! Several people say that 16GB cards are stable. (and 32GB in general are not)