This is new from BSG Automotive:

 

Thanks very much. As usual great stuff from Brian. It's so helpful that he shows the pressures before/after, and how quickly it can really be done. Even if you can't DIY this and have to take it to a shop to pull the system down, at least you can show them this video and not get bamboozled.

 

Wish i had seen this before i changed my compressor back in march. Good find!

 

The video just came out today, so wouldn't have helped you back in March. There is a lot of FEH content on that channel, so it's worthwhile searching his old videos.

 

there is a thread about this on this forum - just a couple of months ago.
you can check your oil level to see if one is low on oil -
maybe adding oil (if needed) will unstick the valve;
but the thread was definitely after march