AE CS5 RAM preview problem

Thanks everyone for feedback and suggestions. I checked the frame rate match and cleaned the caches but the problem unfortunately remains. When RAM preview renders the comp, the frames do show up one by one (as render takes place) but the render stops a few frames before the end of work area (the green bar doesn't reach the very end of work area) and AE starts to play back audio track with no visuals (I have RAM preview set on Loop). After stopping and playing RAM preview again, the green bar jumps to the end of work area (covering 100%) but the playback is again audio track only and no video, the CTI stands still.

My Macs system is MacOS is 10.13.6 (High Sierra) and AE is version 10.0.2.4. I have now tried to install CS5 on 10.12.6 (Sierra) and 10.11 (El Capitan) and on those systems RAM preview works correctly. The problem seems to be if AE CS5 is run on High Sierra and Mojave (tested on 10.14.5).

One workaround I have found is to save RAM preview and then use Quicktime Player to preview video together with audio. Another alternative I have found is to manually drag CTI holding CMD key which plays back both video and audio. But I can't find a way to enable RAM preview to play back as it was supposed to.

Try deleting the Media & Disk Cache in Preferences with a clic in both buttons.

It is hard to say on the limited info but be sure the frame rate matches too while you are checking things.

I was going to suggest that maybe the visibility was turned off but you say you DO see video during RAM preview?  Not sure I understand the difference since RAM preview both renders and plays at the same time, albeit jumpy at first.

Impossible to know. You have not provided any system info, details about your comp, assets used, preview settings and whatnot.

Mylenium