Measure 1.2V at a ADC12 Input Channel

Hello,

if i connect a capacitor (2.2uF) to the ADC12 input channel 8 (MSP430F5419A), and if I spend a little time, I measure a voltage of 1.2 at this port. Where does it come?

Listing of the code ADC12 configuration:

void main(void)
{ 
  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  ADC12CTL0 = ADC12SHT0_8 + ADC12ON;         // Sampling time, ADC12 on
  ADC12CTL1 = ADC12SHP;                     // Use sampling timer
  ADC12IE = 0x01;                           // Enable interrupt
  ADC12MCTL0 = ADC12INCH_8; 
  ADC12CTL0 |= ADC12ENC;
  P5SEL = BIT1;

  while (1)
  {   
     
    ADC12CTL0 |= ADC12SC;                   // Start sampling/conversion   
    while (!(ADC12IFG & BIT0));
  }
}