My understanding is this: if the grouped DAC cannot dynamically tune its clock (like most DAC and our products) outside 44.1/48kHz multiples, especially with the DAC handling full decoding instead of rendering only, MQA integrity will be affected momentarily when Roon tries to sync the grouped zone slave. However, even if the MQA authentication fails momentarily it’s very easy to be missed as it’s re-authenticated very soon unless you’re staring at the MQA LED or front panel for the whole time.