ADRV9009-ZU11EG buffering in GnuRadio

When using GnuRadio with my ADRV9009-ZU11EG SOM, I'm seeing discontinuities in the received data.  They happen whenever the buffer restarts, regardless of buffer size.

Sample rate: 245.76 Msps

LO Frequency: 2300 MHz

Signal generator input: 2300.1 MHz

Is this a known behavior or is there something I can do to get a consistent signal?