AD7177-2, Missing conversions


I'm having a particularly weird issue where I'm not receiving half of the converted values. When streaming conversions, I will receive three (seemingly) consecutive conversions, and then three or four conversions disappear, and then I'll get another three seemingly consecutive conversions. 

I know I'm getting 3 and missing 3 (or 4) because I'm feeding a sine wave in the ADC ch0 input and plotting the converted values on my computer. Every 3 points, there's a jump. 

Does this seem like a familiar issue? Am I somehow not accounting for some cooldown period?

I'm currently operating the chip in:

Ch0 on (Ch1,2,3 are all off)

Continuous Conversion mode (Sync_en off, Err_en = 11)



Default Setup0, Gain0, Offset0

Internal reference

IOCLK = 500Khz