I am having the same problem with my 2007 hybrid accord. I took it to dealership and they could not duplicate problem. It took two weeks to get appointment and the weather warmed up. Birchwood Honda in Winnipeg had no problem say the brakes were okay and if they failed while driving, just bring it back. I called Honda Canada with no luck and they said this problem has never happened before. I had extended warranty and would expire in two and half month. Two days after my extended warranty expired, Honda called and recommending changing vac check valve.