The Spaniard is under growing pressure after eight winless Championship matches in charge ahead of Friday night's huge televised encounter with Sunderland.
Fans chanted for his dismissal during last weekend's 3-0 loss at Swansea City which left Wednesday at the foot of the table. They are the only second-tier side without a win so far this term.
Munoz was asked about whether he had held discussions with chairman Dejphon Chansiri after such a dismal opening to the campaign. He said that details of talks between him and the Owls would remain private.
He commented: "We can change nothing in the past, but learn from our mistakes and right now, our big focus is towards Friday night.
"We have made some big mistakes sometimes. We need to find the balance, one of the key things in the Championship is to try and find the clean sheets and arrive in more dangerous situations for our strikers.
"We are looking at these situations where we need to improve and can only say we are so sorry for our start. It's not the start what we want and what the fans want - and we need to say sorry for that.
"But we can't change the past and can only look at the positive things to try and give all the best in 90 minutes on Friday. We are working very hard for this.
"After, we hopefully have the first win and everything changes.
"The only thing about the players I can say is that we are working very well and this is very important for me. The passion they are showing every day when they come to work in the week is perfect.
"Friday is important for us and it is important to believe we can arrive to the first win. That is what we are working to."