Pentax ME (and Super) lost speed control

[kl122002]

I have a few Pentax ME, ME SUPER lost slow speed control, despite the looked clean and new. The display shows the speed correctly but the shutter just snaped without control .
Is it a common problem? What should I look into ?

 

[Chan Tran]

Do you know what shutter speed it's actually is? Perhaps 1/2000 by any chance?

 

[DREW WILEY]

I was given one of those for free. Looked great but didn't work anymore. I kept it for the lens alone. Hopefully, I'll have a similar lucky find with the more reliable no-nonsense MX model instead.