Hughes is under huge pressure after defeat at home to Newcastle United.
Adam said: “Of course I'm disappointed to see banners against the manager, who has done a wonderful job here.
“Fans have an opinion and we respect that. Times are tough, let's not hide from it, and we're under pressure – that's us as a group, manager, staff and players. We have to take the flak. We thoroughly deserve it at the moment and it's only us who can change it.
“Situations like that don't help but we've got to get ourselves out of the mess we're in.
“Fans backed us during the game but it's still hard to hear at the end because I think he's done a great job. He's transformed this club and hopefully he gets the opportunity to take us to the end of the season.
“We can turn this around. We have got characters in the dressing room and if we can get one or two maybe in the window to liven it up, a couple of fresh faces, and see where that takes us."