Podcasts no longer syncing to iPod touch

I have a 64GB iPod Touch that I sync through iTunes on my iMac. The iPod touch is running on 5.1.1. My iTunes is 12.3.2.35. Neither have been updated in a while. Today when syncing, it tells me that 100+ songs can't be synced, and none of my podcasts. I have never used the Podcast app, I prefer to sync via iTunes, I like managing it that way. Did something change? Are podcasts downloaded to the computer no longer the right format? Can I change this? The latest update it is offering is 6.1.6, do I have to upgrade? I have reset and it still does the same thing.

My iPod is working fine, I know it is a little old but I really don't want to have to buy a new one.

Please assist, if I need to change a setting or need to do something new let me know. Thank you.