this is a total noob qs but i just bought my first pair of iem's (soundmagic pl11) and it didnt come wit any guide so i was wondering how to change the tips that it comes with. i tried to remove the original rubber tip that was on it but it was attached quite firmly and not coming out. so how can i put on the other sizes as this original one is hurting me. forcing it also didnt work it seems attached to the actual flange...