How Can I change channels & nputs on Digitor G4321 TV/Monitor w/out remote?

I've got a Digitor G4321 TV/Monitor that has no remote. I can't change inputs or TV channels for that matter. It is stuck on TV 0 and pushing any of the channel buttons makes no diffrerence. I've purchased a universal remote to see if I can get it going that way but it won't recognise any of the codes in the remote either. Any ideas?