i can imagine that
becasue continent 1 is the most easy, thats for sure.
the other have their own problems. For example continent 3 tends to be easier than 2 since on continent 3 you will have realy powerhouse units and your army is in egneral much more epierienced, so the enemy "expierience" kicks way less in.
in continent 2 you may have get a slightly better army via specialized research, but your troops are not that much expierienced and the enemy units will have a lot of expierience.
btw, its really worth to serach the internet about information about Fabntasy General - i will post some here.
to solve your problem i suggest just to try the version available here at Abadonis. play the Music from an external programm
the soundtrack is also available in the internet, btw