New Thermostat installed but compressor comes on immediately

I have a new Insteon Thermostat that I’m using to replace my prior Honeywell t-stat. This is installed to a relatively new HVAC system (both AC and Heat) that DOES have a “c” wire. I’ve attached the wires correctly in that the terminals on the furnace control side are matched to the terminals on the t-stat by “code” (meaning G goes to G, Y goes to Y, W goes to W, C goes to C and R goes to R).

I’m not quite sure that the secondary 24VAC is wired into all of this correctly and perhaps that’s why the compressor comes on as soon as the system is energized.

Below is a photo of the wiring diagram on the furnace. NOTE: On the furnace terminals, the wire terminating into “R” is red, the wire into “Y” is yellow, the wire into “G” is green, the wire into “C” is blue, and the wire in “W” is white; you’ll note that this is maintained on the t-stat side as well.

And here is the photo of the inside of the thermostat:

Any help anyone can offer on how or what might be wrong would be most appreciated.

TRANSFORMER NOTE:
The red wire off of the 24VAC transformer is “spliced” into the red wire going between the furnace and the t-stat.
Similarly, the white wire off of the transformer is spliced into the blue (common) wire between the furnace and the t-stat.
I have a feeling this is the problem, but I’m not sure how to “fix” it.