I got some rubber tipped/silver thread cartos during the week. I have been using 2, one worked ok right away the other one is producing very weak vapor, no th. The later one has been in use for about 48 hours or so. I'm using 25 drops. Should I just throw it out versus contuning to waste liquid on it? What is the normal brean-in time for these? I decided to go with cartos since they are cheap and I was getting frustrated with regular atty's going out on me all the time, also for use while driving since I only drip. Thanks in advance.