diff --git a/distrho/src/DistrhoPluginVST3.cpp b/distrho/src/DistrhoPluginVST3.cpp
index b81c59593..6883bfe5c 100644
--- a/distrho/src/DistrhoPluginVST3.cpp
+++ b/distrho/src/DistrhoPluginVST3.cpp
@@ -1446,13 +1446,17 @@ class PluginVst3
            #if DISTRHO_PLUGIN_NUM_INPUTS > 0
             if (data->inputs != nullptr)
             {
-                for (int32_t j = 0; j < data->inputs->num_channels; ++j)
-                {
-                    while (!fEnabledInputs[i] && i < DISTRHO_PLUGIN_NUM_INPUTS)
-                        inputs[i++] = fDummyAudioBuffer;
+                for (int32_t b = 0; b < data->num_input_buses; ++b) {
+                    for (int32_t j = 0; j < data->inputs[b].num_channels; ++j)
+                    {
+                        DISTRHO_SAFE_ASSERT_INT_BREAK(i < DISTRHO_PLUGIN_NUM_INPUTS, i);
+                        if (!fEnabledInputs[i] && i < DISTRHO_PLUGIN_NUM_INPUTS) {
+                            inputs[i++] = fDummyAudioBuffer;
+                            continue;
+                        }
 
-                    DISTRHO_SAFE_ASSERT_INT_BREAK(i < DISTRHO_PLUGIN_NUM_INPUTS, i);
-                    inputs[i++] = data->inputs->channel_buffers_32[j];
+                        inputs[i++] = data->inputs[b].channel_buffers_32[j];
+                    }
                 }
             }
            #endif
@@ -1465,13 +1469,17 @@ class PluginVst3
            #if DISTRHO_PLUGIN_NUM_OUTPUTS > 0
             if (data->outputs != nullptr)
             {
-                for (int32_t j = 0; j < data->outputs->num_channels; ++j)
-                {
-                    while (!fEnabledOutputs[i] && i < DISTRHO_PLUGIN_NUM_OUTPUTS)
-                        outputs[i++] = fDummyAudioBuffer;
+                for (int32_t b = 0; b < data->num_output_buses; ++b) {
+                    for (int32_t j = 0; j < data->outputs[b].num_channels; ++j)
+                    {
+                        DISTRHO_SAFE_ASSERT_INT_BREAK(i < DISTRHO_PLUGIN_NUM_OUTPUTS, i);
+                        if (!fEnabledOutputs[i] && i < DISTRHO_PLUGIN_NUM_OUTPUTS) {
+                            outputs[i++] = fDummyAudioBuffer;
+                            continue;
+                        }
 
-                    DISTRHO_SAFE_ASSERT_INT_BREAK(i < DISTRHO_PLUGIN_NUM_OUTPUTS, i);
-                    outputs[i++] = data->outputs->channel_buffers_32[j];
+                        outputs[i++] = data->outputs[b].channel_buffers_32[j];
+                    }
                 }
             }
            #endif
@@ -2802,6 +2810,7 @@ class PluginVst3
 
             // d_debug("setAudioBusArrangement %d %d | %d %lx", (int)isInput, numBuses, busId, arr);
 
+            size_t nth_speaker = 0;
             for (uint32_t i=0; i<numPorts; ++i)
             {
                 AudioPortWithBusId& port(fPlugin.getAudioPort(isInput, i));
@@ -2812,18 +2821,9 @@ class PluginVst3
                     continue;
                 }
 
-                // get the only valid speaker arrangement for this bus, assuming enabled
-                const v3_speaker_arrangement earr = getSpeakerArrangementForAudioPort<isInput>(busInfo, port.groupId, busId);
-
-                // fail if host tries to map it to anything else
-                // FIXME should we allow to map speaker to zero as a way to disable it?
-                if (earr != arr /* && arr != 0 */)
-                {
-                    ok = false;
-                    continue;
-                }
-
-                enabledPorts[i] = arr != 0;
+                v3_speaker_arrangement earr = (uint64_t)1 << nth_speaker;
+                enabledPorts[i] = 0 != (arr & earr);
+                 ++nth_speaker;
             }
         }