Signal goes between full and none for no reason. topic

I recently have had an issue, and this only occurs on CyanogenMod (11 & 12). Basically, I'll be using my phone normally, but I'll notice my signal will go from full bars to no service every 30 seconds or so, it seems. That interval is to give you an idea. This issue does not occur on any other ROM that I've used (Cataclysm, PA, Rastapop, Stock, so forth). I've tried adding my APN as a fix but didn't seem to do anything. Information:

Sprint MVNO (Ting), running barebones CM, no gapps.

I'd love to get this solved, if anyone has ever figured this out. I've searched on Google and have seen no resolution, but have seen other's with the issue.