On which version did you initially setup your tunnel ?There is may be some steps not properly done on a native 1.0.4.17.Or did you mind to provide me your saved configuration to compare ?Thanks
It might explain why I didn't succeed to setup my HE IPv6 tunnel on 1.0.6.6.But even after downgraded to 1.0.4.17 and factory reset the device, I'm still unable to have a working IPv6 tunnel.If have followed this how-to and take in account the Joerge...