X-H1 images are decoding correctly for me here. Please email me at support@gentlemencoders.com – I will send you a link to upload an image so I can try to reproduce the problem.
Also, what version and platform are you using (macOS / iOS and the complete version number of the OS)? I’m finding issues in older versions of macOS & iOS. Those problems disappeared when I went to macOS 11.4 and iOS 14.6.