Scan frequences RSSI

[Amigo]

I want to monitor NRF radio channell's RSSI to switch on "free" channel. How to make it properly?

This is my code:

if(rx_q_flag == true){
				err_code = esb_init(RX, radio_channel);
				APP_ERROR_CHECK(err_code);
			
				err_code = nrf_esb_start_rx();
				APP_ERROR_CHECK(err_code);
				
				//NVIC_DisableIRQ(RADIO_IRQn);
				//NRF_RADIO->EVENTS_DISABLED = 1;
				//NRF_RADIO->TASKS_RXEN  = 1;	

				for(int i=0; i<10; i++)
				{	
					NRF_RADIO->TASKS_RSSISTART = 1;
					rssi_average[i] = (uint16_t)(NRF_RADIO->RSSISAMPLE);
					while(NRF_RADIO->EVENTS_RSSIEND == 0);
					NRF_RADIO->TASKS_RSSISTOP = 1;
					nrf_delay_us(500);
				}
				max = rssi_average[0];
				for(int i = 0; i < 10; ++i)
        {
            if(rssi_average[i] < max)
            {
                max = rssi_average[i];
            }
        }
				RSSSI_BUF[radio_channel] = max;
				if(RSSSI_BUF[radio_channel] < 50){
					sprintf((char*)textbuff, "CH: %d RSSI: -%d dBm\r\n", radio_channel, RSSSI_BUF[radio_channel] );
					Serial_Print(textbuff);
				}
				NRF_RADIO->TASKS_RXEN  = 0;	
				
				if(radio_channel++ >=125) 
				{
					radio_channel=0;
					rx_q_flag = false;
				}
			}

I take an array with max negative RSSI but it always looks like garbadge.

[Jørgen Holmefjord]

What is wrong with the RSSI values?