ESS problem with firmware 3.66

Has anyone else noticed ESS problem with firmware 3.66. I have Multiplus 2 GX and it work fine with firmware 3.62. I updated firmware to 3.66 and then ESS not work anymore. DESS works still like before. All settings was fine, but inverter never discharged in ESS mode with this firmware. I installed firmware 3.62 again and everything work well again. Am I only one who have issue like this? What could be reason about that?