Continuous ADC acquisition

We are testing BF518F EZ board.

The function we want to achieve is to acquire ADC data at 1kHz continuously (we are using the AD7266 on the evaluation board for now).

The DSP will perform other tasks as well (the one we are testing is to communicate to host through Ethernet randomly).

We created two tasks using OSTaskCreate, one for the ADC acquisition, the other for other tasks including the Ethernet communication.

In the ADC task, we have a continuous running 1ms timer using      OSTimeDly, then read the data every 1ms.

The ADC acquisition runs OK by itself.

However, if the host sends Ethernet communication to the DSP, the ADC acquisition will be paused for some time (~6ms).

How can we eliminate the pause?

Should we use other methods to generate the timer? Or there are some settings we should change?