No Videostream Android to iOS

using NC20, current Android and iOS clients.
While videocalls from iOS to Android works ok - i.e. both sides can see and hear each other - videocalls from Androidclient to iOS doesn’t. Notification on iOS says incoming audiocall (Nextcloud Talk-Audio…) despite having started a videocall.
Is this a bug caused by Android or iOS client? How to fix?
On both devices access to camera and mic have been granted (obviously)

Some additional information:
Useragent strings sent by clients are: “Mozilla/5.0 (iOS) Nextcloud-Talk v11.0.1” and “Mozilla/5.0 (Android) Nextcloud-Talk v11.1.0” respectively. Another ua-string used by iOS version is “NextcloudTalk/1 CFNetwork/1220.1 Darwin/20.3.0”

NC version is, Talk app on server is 10.0.6 running on Centos 7 with php version 7.4.16

log is flooded with lines containing:
“message”:"/appinfo/app.php is deprecated, use \OCP\AppFramework\Bootstrap\IBootstrap on the application class instead.