problem gufw

Hello, my gufw runs at startup, the rules work fine except that gufw does not let anything pass. For example, when I start my computer and I want to watch the TV with VLC I first have to deactivate temporarily gufw, choose a channel then reactivate gufw and it lets pass VLC but if I want to change the channel, gufw me blocks VLC And I am obliged to stop gufw again and then start it to watch the new channel. It's not all practical. Almost the same with firefox, if I want to surf on the Internet then it makes me deactivate then reactivate gufw, same for Thunderbird, impossible to send messages without stopping gufw but I can receive them.
S-please you have an idea?