YOu don't write which MSP you use. Most of the 5x family or newer MSPs have an internal pull-up on RST (40-60k). (on the 5438 and some others it isn't enabled on power-up, making it useless) In these cases, the external resistor is not only superfluous, it effectively halves the pulldown capacitance. Take a look at your VCC with a scope. How long does it take to settle? With the internal resistor, the 47k/100n/1k construct won't work effectively anymore. But you can simply try 1k/100nF in series from RST to GND.
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