Weird Teensy 4.1 behavior on power up


my teensy 4.1 was working perfectly, I might have done something wrong as I was connecting and disconnecting some signal for diagnostics and changing some things around my breadboard.

Bottom line is that it works but it keeps happening that on power up the red led flashes 4 times, it does this a random number of times and then it runs my code, but while it flashes the computer cannot see it, the button on the board stops the flashing but it doesn't take it to programming mode...

it feels like it sometimes needs to warm up.... I don't know for sure.

I am not very experienced in electronics but trying to learn as much as possible.... I do have a scope and multimeter, will start to test around for voltages, but if anybody can point me as to why this might be happening, I would appreciate it.

will post updates when I do some testing around.
thanks for the reply, Paul, will check it out, I'm really enjoying using teensy and learning as much as I can... weird enough today I got back home and plugged it a couple of times and hasn't failed at all... it's going straight into executing my code without blinking the red LED at all...
I will keep posting if I figure anything out.