Volumio CAN handle MQA, but only under some circumstances:
You need to have a USB DAC that is MQA compatible. For example, a Pro-Ject Pre Box S2 Digital can play any MQA file
With a compatible USB DAC, volume must be set at 100
In any other condition, MQA will not work on Volumio. This is mainly because we can't incorporate the MQA software decoder into Volumio as we will violate MPD's GPL license.