Greetings. I have an HC-250 based system - in service now x 4 years. Any warranty is long since expired. As a Geek was curious regarding the guts. In addition, I've had problems with ComposerME (supposed to allow control over media sources - but with over 3TB music and video files, the ME database clogged up my HC-250 memory with music folder images and other garbage). I do have ComposerHE - but it does NOT allow data file cleanup - I have to pay a dealer/installer to do that with Composer Pro. In addition, there are internal conflicts as my current OS is 2.9.1 but some files are 2.9.0. I need to update my version of Epic Echo controller - from ver 110 to the current Ver 180 (which I've downloaded) - but of course can't install. Dealer says (of course) will take a service call visit (Ka Ching) - So - - Anyway: I noticed a CR-3032 backup battery - so while system powered up, I replaced that with a new one (old one has been in there x 4 years) AND I noticed a 4GB SanDisk Micro-SD card. I plugged it into my PC - and of course whatever format is on the card could NOT be read by my PC. In addition - not even my disk clone program could see the SD card. I suspect the card is formatted with some variant of Linux or possibly an even more obscure OS ?? - Anyway - before my dealer comes out to "re-flash" my system (yes - I will use ComposerHE to back up my configuration first) Should I consider replacing the 4GB MicroSD card with an 8 or even 16GB card ??