VMU turns-off and on

[stylus]

Hi all

Started playing my dreamcast after 3 or 4 years of not playing it.

I have 3 working controllers, 2 vmus.

Problem:

one of the vmu's, when plugged in, turns on and off as soon as it is inserted into any of the three controllers. It does this non-stop unless it is removed -- it has no batteries inside.

the other vmu works, but after playing a few minutes, it turns off and goes back on. When it's stable, and I try to save, it turns off at the moment I save and comes back on. this vmu also has no batteries in it

What is the issue i'm experiencing here? is it a vmu issue, a controller issue?