ALC889_FIXUP_MBA11_VREF,
        ALC889_FIXUP_MBA21_VREF,
        ALC889_FIXUP_MP11_VREF,
+       ALC889_FIXUP_MP41_VREF,
        ALC882_FIXUP_INV_DMIC,
        ALC882_FIXUP_NO_PRIMARY_HP,
        ALC887_FIXUP_ASUS_BASS,
                                  const struct hda_fixup *fix, int action)
 {
        struct alc_spec *spec = codec->spec;
-       static hda_nid_t nids[2] = { 0x14, 0x15 };
+       static hda_nid_t nids[3] = { 0x14, 0x15, 0x19 };
        int i;
 
        if (action != HDA_FIXUP_ACT_INIT)
                .chained = true,
                .chain_id = ALC885_FIXUP_MACPRO_GPIO,
        },
+       [ALC889_FIXUP_MP41_VREF] = {
+               .type = HDA_FIXUP_FUNC,
+               .v.func = alc889_fixup_mbp_vref,
+               .chained = true,
+               .chain_id = ALC885_FIXUP_MACPRO_GPIO,
+       },
        [ALC882_FIXUP_INV_DMIC] = {
                .type = HDA_FIXUP_FUNC,
                .v.func = alc_fixup_inv_dmic,
        SND_PCI_QUIRK(0x106b, 0x3f00, "Macbook 5,1", ALC889_FIXUP_IMAC91_VREF),
        SND_PCI_QUIRK(0x106b, 0x4000, "MacbookPro 5,1", ALC889_FIXUP_IMAC91_VREF),
        SND_PCI_QUIRK(0x106b, 0x4100, "Macmini 3,1", ALC889_FIXUP_IMAC91_VREF),
-       SND_PCI_QUIRK(0x106b, 0x4200, "Mac Pro 5,1", ALC885_FIXUP_MACPRO_GPIO),
+       SND_PCI_QUIRK(0x106b, 0x4200, "Mac Pro 4,1/5,1", ALC889_FIXUP_MP41_VREF),
        SND_PCI_QUIRK(0x106b, 0x4300, "iMac 9,1", ALC889_FIXUP_IMAC91_VREF),
        SND_PCI_QUIRK(0x106b, 0x4600, "MacbookPro 5,2", ALC889_FIXUP_IMAC91_VREF),
        SND_PCI_QUIRK(0x106b, 0x4900, "iMac 9,1 Aluminum", ALC889_FIXUP_IMAC91_VREF),