Why are plants turning hermie on me and getting seeds

I have been doing this for about a year or two with great results until lately.. My last few plants and I noticed a few plants now for some reason are turning hermie on me and are getting seeds, I dont get it, I have changed nothing but everytime I see one getting wierd its gone and I have eliminated several strains already in my search to figure out why ! any help would be awesome.....

Thanks
Og

could be stress from a light leak. but i would think of the most recent strain u added and inspect it closely for male flowers. The male flowers that ur gonna wanna look for look like little bananas that form on the buds, usually towards the top on the main colas. Hope this helps, you should look at pictures of hermis on this site or google and u will see what I mean, they are hard to spot but once you find one, you will know which strain is the culprit. This could be because of a light leak or stress, or also just because of plain hermi prone genetics. It happens a lot with feminized seeds if thats what you are running.

Thanks Man, they were clones, but were they came from may be suspect.....I just got pissed and killed a few that I think may be headed the wrong way....lessons learned the hard way.............Thanks

As mentioned look for rogue male flowers amongst the bud and as well always monitor the lower growth for possible male flower formation amongst the branching , this is most common with landraces but is also found with hermie clones