diff --git a/local/recipes/system/redbear-ecmd/source/src/main.rs b/local/recipes/system/redbear-ecmd/source/src/main.rs
index ead3d9ac16..0c1c2968c3 100644
--- a/local/recipes/system/redbear-ecmd/source/src/main.rs
+++ b/local/recipes/system/redbear-ecmd/source/src/main.rs
@@ -110,29 +110,35 @@ fn main() {
     let data_iface = data_iface.expect("No CDC ECM data interface found");
 
     // Find bulk IN + bulk OUT on the data interface, and optional
-    // interrupt endpoint on the control interface.
+    // interrupt endpoint on the control interface. xhcid keys endpoints
+    // by GLOBAL index across all interfaces of the configuration (see
+    // xhcid PortState::get_endp_desc / endpoint_states) — the USB
+    // endpoint address number only coincides with that index when the
+    // device's addresses are sequential in enumeration order, so count
+    // endpoints in configuration order instead.
     let mut bulk_in_num = 0u8;
     let mut bulk_out_num = 0u8;
     let mut int_num = 0u8;
 
     for conf_desc in desc.config_descs.iter() {
+        // xhcid indexes endpoints within the selected configuration only;
+        // reset the counter per config and keep only the selected one.
+        let mut config_num = 0u8;
         for ifd in conf_desc.interface_descs.iter() {
-            if ifd.number == data_iface {
-                for ep in ifd.endpoints.iter() {
-                    if ep.attributes & 0x03 == 0x02 { // bulk transfer type
-                        match ep.direction() {
-                            EndpDirection::In => bulk_in_num = ep.address & 0x0F,
-                            EndpDirection::Out => bulk_out_num = ep.address & 0x0F,
-                            _ => {}
-                        }
+            for ep in ifd.endpoints.iter() {
+                config_num += 1;
+                if conf_desc.configuration_value != conf_val {
+                    continue;
+                }
+                if ifd.number == data_iface && ep.attributes & 0x03 == 0x02 { // bulk transfer type
+                    match ep.direction() {
+                        EndpDirection::In => bulk_in_num = config_num,
+                        EndpDirection::Out => bulk_out_num = config_num,
+                        _ => {}
                     }
                 }
-            }
-            if ifd.number == ctrl_iface {
-                for ep in ifd.endpoints.iter() {
-                    if ep.attributes & 0x03 == 0x03 { // interrupt transfer type
-                        int_num = ep.address & 0x0F;
-                    }
+                if ifd.number == ctrl_iface && ep.attributes & 0x03 == 0x03 { // interrupt transfer type
+                    int_num = config_num;
                 }
             }
         }
diff --git a/local/recipes/system/redbear-usbaudiod/source/src/main.rs b/local/recipes/system/redbear-usbaudiod/source/src/main.rs
index 3dc081faf3..05c9ed1bd5 100644
--- a/local/recipes/system/redbear-usbaudiod/source/src/main.rs
+++ b/local/recipes/system/redbear-usbaudiod/source/src/main.rs
@@ -188,24 +188,34 @@ fn main() {
         return;
     }
 
-    // Find isoch endpoints on the streaming interface
+    // Find isoch endpoints on the streaming interface. xhcid keys
+    // endpoints by GLOBAL index across all interfaces of the
+    // configuration (see xhcid PortState::get_endp_desc /
+    // endpoint_states) — the USB endpoint address number only coincides
+    // with that index when the device's addresses are sequential in
+    // enumeration order, so count endpoints in configuration order.
     let mut isoch_in_num = 0u8;
     let mut isoch_out_num = 0u8;
     let mut max_pkt_size = 0u16;
 
     for conf_desc in desc.config_descs.iter() {
+        // xhcid indexes endpoints within the selected configuration only;
+        // reset the counter per config and keep only the selected one.
+        let mut config_num = 0u8;
         for ifd in conf_desc.interface_descs.iter() {
-            if ifd.number == as_iface {
-                for ep in ifd.endpoints.iter() {
-                    if ep.attributes & 0x03 == 0x01 { // isoch transfer type
-                        if ep.max_packet_size > max_pkt_size {
-                            max_pkt_size = ep.max_packet_size;
-                        }
-                        match ep.direction() {
-                            EndpDirection::In => isoch_in_num = ep.address & 0x0F,
-                            EndpDirection::Out => isoch_out_num = ep.address & 0x0F,
-                            _ => {}
-                        }
+            for ep in ifd.endpoints.iter() {
+                config_num += 1;
+                if conf_desc.configuration_value != conf_val {
+                    continue;
+                }
+                if ifd.number == as_iface && ep.attributes & 0x03 == 0x01 { // isoch transfer type
+                    if ep.max_packet_size > max_pkt_size {
+                        max_pkt_size = ep.max_packet_size;
+                    }
+                    match ep.direction() {
+                        EndpDirection::In => isoch_in_num = config_num,
+                        EndpDirection::Out => isoch_out_num = config_num,
+                        _ => {}
                     }
                 }
             }