Correct gcode for a tool change?

I seem to get a fast Z run up to top which then throws an alarm with this code. On the second or 3rd tool change.

Is there something wrong/missing from the code? What am I doing wrong? It runs ok w/o a bit as a test. When I move the router to change the bit the issue sometimes occurs.

Here is the tool change block

M05. <=== stop spindle
T{x} M06 <==== prompt change to tool {x}
M03 S10000 <=== turn on the spindle

where {x} = 1…4

File is small and has 4 drill sizes.

(Also got a USB missing message, first time for that)

( PCB drills )
( Generated by Carbide Copper )
( Material Size )
( X= 152.400, Y= 101.600, Z= 1.580 )
()
G17
G21
G54
G90
M05
T1 M06
M03 S10000
G00 X92.250 Y50.750
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X92.250 Y4.250
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X4.250 Y4.250
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X4.250 Y50.750
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
M05
T2 M06
M03 S10000
G00 X35.881 Y47.794
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X30.881 Y47.794
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X48.285 Y47.837
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X43.285 Y47.837
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X60.688 Y47.752
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X55.688 Y47.752
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X73.092 Y47.879
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X68.092 Y47.879
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
M05
T3 M06
M03 S10000
G00 X62.210 Y25.400
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X59.670 Y25.400
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X59.670 Y33.020
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X62.210 Y33.020
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
M05
T4 M06
M03 S10000
G00 X48.113 Y33.719
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X48.113 Y26.479
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X39.033 Y32.893
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X31.793 Y32.893
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X72.624 Y32.829
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 X72.624 Y40.069
G00 F750 Z0
G01 F15000 Z-1.780
G00 Z3.000
G00 Z3.000
M05
M30
%