Hello Frederic, both my 44 and Hp came a little higher. I believe they are designed this way. If you play with a lot of dynamics, when played at low volume, notes will be a little sharp, but if you play a little louder you will notice that pitch will sound more in tune. It is not recommended that you play loud or blow extremely hard consistently as this can cause a reed to crack in time. If you are out of tune a few cents, play for 10-15 minutes and check your tuning at a moderate volume and see if it has changed. If your melodeon is out of tune octave to octave, then the you should tune ore return it if you do not feel confortable tuning it. Some stores will not replace them if you have played it for a while so contact the seller and let them know right away that it came out of tune.
I hope this helps.