... one of the adapters is white (SKU 289-4005 or 289-4006) and the others are black. Don't think Menards currently sales the white one ...
They no longer sell those adapters because they were of the unregulated ilk meaning the voltage output varied depending on how many buildings were hooked up. There were several OGR threads a few years back decrying this as many guys reported buildings failing from over-voltage. Menards has since replaced them with regulated adapters. The first thing I'd do is replace your unregulated adapter(s). Here's a photo from one of the earlier OGR threads showing the new SKUs - prices may be out of date.
Menards now seems to publish mA requirements on their newer products. But, if you search older OGR threads you'll find grousing about Menards buildings with unstated mA requirements. To that end there was an effort to measure the mA requirements for various buildings to allow us to estimate the requirements based on number of LEDs, number of "neon" animated signs, spinning fan motors, etc..
As John suggests, if you don't have published mA requirements use 20 mA per LED. Based on the description of Grandpa's House, I'd think it requires a few hundred mA at most.
