Yes, I think the message to International Kindle owners has to be: don't expect generic "USB chargers" to work with the Kindle - some may, but a lot of people are reporting the same issues and I have experienced them myself. see this thread:
https://www.mobileread.com/forums/showthread.php?t=59692
I've also noticed that the Kindle is picking up a very weak wireless signal here - often just 1-2 bars, even though there should be full 3G coverage in our part of Luxembourg.
Apart from these 2 issues, my Kindle works just fine for reading.