We cannot recreate that behavior here with Pipeline so we cannot speak to a possible cause other than perhaps bouncing something who's audio path is using Pipeline and the original clip getting muted by default after a bounce.
If you can provide steps to recreate please create a support ticket and list the steps to recreate so that a tech support representative can try to confirm it and perhaps log it with the development team for review.
If you do that, please include all relevant details, OS, Studio One version, etc.