Was that with 2016 Pro Ones or the new 2019 Pro Ones? I’ve used the 2016 version for many miles and love them. Purchased the 2019 version with the addix compound as soon as they released and I am also seeing sealant slowly bubbling out. They still work and the hold pressure well, I just never had this issue with the 2016 version. Although the 2019’s feel more plush and better in my hands, I’m liking the 2016 better with the one star compound and microskin. Never had sealant seep out with the 2016’s.
What sealant are you using? I am using finish line.