Multicam clip don't play in angle viewer when playing from the project timeline

I have been editing the same multicam TV show every week for 6 months using the same cameras, resolution, etc. and all of a sudden FCP X stopped working for being able to play the camera angles in the angle viewer while playing from the timeline in the project.

I tried to take your advice and switch over to using proxie media but when I did it said media can't be found. Is theer a way to generate proxie files after the footage has already been imported or do I have to re-import?

Thanks for your help and do you have any idea why my system may have stopped working all of a sudden?

I thought I would mention that even previous projects that used to play fine in the angle viewer have stopped playing now. Any ideas anyone?

I created proxy clips, thanks to your suggestion via transcode media, I clicked use proxy media but it still said proxy missing in the multicam clip so I then created a new mulicam clip with use proxy media clicked and the missing proxy warning went away but unfortunately I still have the same result when trying to view the multicam clips, no movement of the clips in the angle viewer when playing from the timeline in the project.

I previously trashed the preferences, repaired permissions, and rebooted. The only thing that has happened recently is that I had to load FCP 7 a few days ago to work on an old project. I used to have FCP X and FCP 7 on separate partitions but now they are on the same drive and coincidentaly when I think about it is when multicam in FCP X stopped working.

I actually did it the other way around. I had problems installing FCP 7 so it was suggested that I put FCP X in it's own folder so that's how I did it. Do you think it's better to put FCP 7 into it's own "Studio" folder and then re-install FCP X? and if so, do I just put the previous FCP X in the trash and then re-install it from the app store?

I appreciate all of your help. If you don't mind I have another question about how to specify the duration of a clip in the event browser after the in point has been selected. I'm sure I've done it before but forget how. For instance I want to be able to skim and select an in point and then have the out point go 1 second after that.

I put FCP 7 in a separate folder and re-installed FCP X and still have the same problem. Does anyone ahve any ideas?