Um, that's a problem with some of those pod systems, there sometimes isn't much to be done about flavor issues. I guess it's possible that your device (is it fixed wattage?) and coil (are there different coil options?) aren't vaping it at a temperature that is acceptable for the juice, so you get bad flavor.
I suppose your coil could be burnt? If it tastes "like ash" maybe it needs to be replaced, or the whatever that device uses to vaporize the eliquid (sorry I don't use pods, at all). If there's an airflow adjustment, you could try more air. If there is a higher resistance option, I guess you could try that?
Hopefully someone more familiar will be along, but I'd think off the top of my head that it just is overheating your juice, that and/or the possibility that your coil may have burned out and may need replacement.
Good luck,
Anna