I upgraded my mi box (not s) to pie and lost HD audio in kodi I managed to downgrade to an earlier Oreo build 2303 and the hd audio is back but have lost the refresh rate auto switching capability I would like to upgrade to build >2550 (but keep Oreo!} which enables the auto frame rate switching and also has dts hd and dolby hd support

Doing an ota update says no new updates available and I can't seem to find a manual zip update online

Does anyone have a link where to get the ota zip file?