Airpods stop playing audio after a while

So a few minutes ( sometimes 20, sometimes 40, or 10 minutes) after I put my airpods on they stop streaming the sound (they don't disconnect they just play no sound at all, I know this because the videos or music don't pause) I have to take them off, wait a little and then put them back on and only by then they will work, but eventually this keeps happening, wether im on my iMac or my iPhone 7 Plus, they are quite new and never leave the house, never did I drop them so I can't find any reason to why they are doing this, I would really appreciate any kind of help, I need to know what can I do. They didn't do this in the first 2 months so this is quite recently.
Ps. I bought them online on www.apple.pt so I'm not sure if they have warranty,
Thank you.