SD Card

[charliep]

I am using the STM32 board as a datalogger using a 8GB microSD card- it passed all initial tests perfectly, however a short time after being installed in the test rig SD.begin(25); started throwing up errors and is no longer able to write to the card.
No code was changed between the functioning and non-functioning runs, and I have been trying to get to the bottom of it for the last 5 hours or so. A quick response would be appreciated as I have limited time in the wind tunnel for testing.
Thanks

[olimex]

check your power supply for glitches which may interference with card write signals

[charliep]

power supply seems to be fine, a single cell LiPo battery (it's a rotating rig).
about 1 run in 20 it works (OP was on run 17) - there are currently 2 competing theories in the lab, either the contacts are dodgy. My theory is that the 2 contacts in the SD card housing, which I think are there to provide a 'Card present' signal are being forced to contact, despite the card being present, by the rather tight fit of the rig on the board. If this is a possibility would removing the 2 contacts fix this?
Sorry if this seems like a bit of a dumb question, my specialization is in aeromechanics and this is the first electronic's I've done in years.