I've tried a bunch of rta's and rda's over the last 6 months and the siren v2 is one of my favorites but I have a problem with it that I just can't figure out. After about a tank of juice it starts to give off a rubbery flavor. I'm certain it's not a dry hit burnt taste but a distinctive rubbery taste. Cleaning it with an ultrasonic cleaner will clear up the rubbery flavor but it always eventually comes back. I think maybe an o-ring or the top silicone seal is seeping flavor into the vape somehow? I've tried different coils, juices, drip tips etc. but haven't been able to pinpoint where the problem is. It's one of my favorite vapes in terms of flavor and airflow but I'm at a point where I'll have to stop using it. Anyone else have this problem?