PIC18F4685 Sensitivity issue on Protoboard

[micro9000]

Alright I've gone over all of my connections, which were soldered on to the protoboard. I have a 9V battery delivering power to a LM7805 5V voltage regulator, which then gets split off to both VDDs. The VSS is soldered at a common point to the Voltage regulator, along with both VSS's and the LED's ground. I have also tied that ground to a metal plate. Now, I have 8 LEDs, each with 1/2 W 100ohm current limiting resistors coming out of RA0 through RA7. Now the problem is the program runs, but it dies out randomly. Sometimes it goes for 10seconds, and other times it can go for about 1-5 minutes. I then have to play around with the board and sometimes reconnect the 9V battery. I don't think it's the connections, I have gone over them a few times already. What am I doing wrong. This is my first time actually building a circuit like this onto a protoboard.

Something I also noticed was that the sensitivity I am experiencing now, happened during when I was testing the circuit in the bread board. However, the arbitrary die outs occurred less frequently. Do I need a cap or something? From your experience how did you stop such sensitivity? Thanks in advance.

EDIT:
To add to the confusion. At times I walk up to the board and it goes off and other times I walk away from it, it turns on. Are the remaining pins that sensitive to static or something? Could it possibly be the input? The other pins are not covered, but there isn't any other object near them except myself? Would covering up the pins with electrical tape help?

 

[Pommie]

A couple of suggestions,
Add decoupling capacitors near the power pins. 100nF ceramics are best.
Use a 1k - 10k resistor from MCLR to Vdd.

Mike.

 

[micro9000]

Thank you Pommie for the response. I'll give that a go and let you know how it goes. Thanks

Edit:
I placed a 2k resistor from VPP to VDD and it is much more stable. I guess that makes sense to tie it to a 5V source since reading a logic zero would make it reset. And, since I didn't have VPP grounded it would just reset the uC randomly. So far, so good.

Edit2:
About 40min and it's still stable. Thanks a bunch Pommie!