Its not an uncommon sympton. It has happened to me with numerous gadgets and devices, not only with cards......
Most notable example are chargers, especially for mobile phones or PDAs. Same thing goes for hands-free (chargers and their own connection with the mobile phone). All the above require either some *special* pressure, or you have to plug it in in a specific angle, otherwise they dont make proper contact......
Seems like manufacturers are starting to get sloppy.......no other way to explain it