I have a sony a7rIII and a 1.4 Gmaster 85 lens. Things were fine, then I bought a 24-105 lens, played with it for several months, then I put the Gmaster back on and now I can't change the aperture in manual mode. If I put it in A priority it seems to be ok. But I rarely use that. Has any one seen this before. 'can't figure it out.