i've the same problem, i get the island detect warning every day a few time.
the error occurs to full or half hours. today at 10:30, 11:00, 12:00, 12:30, 13:00, 13:30, 16:00, 16:30, 17:00
the installation is made from a professional, the system was measured (earth resistance, insulation etc)
i have s smal 3kw SMA Tripower inverter next to the MPP MPI Solar Hybrid 10k and the sma works without a problem.