Anyone do VFD troubleshooting/repair?

I've got two imported (Chinese) VFDs that could use some help.

One of them (Huanyang HY02D223B) worked great for 8 months and then one day "pop!" and the faint smell of smoke was in the air.

The second one (Xin Ye YP-C2D2-2G) never quite worked right. It would work well for periods, then shut down randomly. Other times it would not power up at all. I suspect a bad solder joint or problem with the control panel.

I realize that fixing these requires very specialized skill and expertise. I'm wondering if there is anyone here that has some decent knowledge and experience - who would like to take a stab at getting one or both of them working?

I could compensate you for your time or trade one of the units for getting the other one functional. I could send them both back to China for repair, but the shipping costs don't really justify it.

PM with any ideas or interest. Thanks.

Steve