Antonio Cassano, the team's enfant terrible, has been acting up of late, getting involved in a verbal spat with a fan at Samp's training ground.
But Palombo says: "It always happens even in the past with Novellino and Mazzarri that in difficult moments rumours of every kind spread, but they are all without foundation.
"We have had a black out period with two ugly defeats, one in the derby and the other against Milan, to which we also have to add the knock out in the Coppa Italia at the hands of Livorno.
"Now it's up to us to start again with less chatter and more pedaling on the pitch. We need to wake up again as soon as possible. But in the last few days I have seen that things are going better in training."