You probably will have to dig deeper Eric.
The 555 is only supplying the pulse timing and or pulse
width modulation for something else to handle the
larger switching current.
On it's own a 555 can only supply milliamps from it's
output, most configurations that's Pin 3.
I'd say the problem is associated with the device switching
the large currents.
It's a pity you can't show a circuit or maybe even take a close
up pic of the PCB both sides.
One of us might spot something obvious, albeit, hands off
Steve