diff --git a/web/src/components/config-form/sections/BaseSection.tsx b/web/src/components/config-form/sections/BaseSection.tsx
index 6eb7640453..7727b92201 100644
--- a/web/src/components/config-form/sections/BaseSection.tsx
+++ b/web/src/components/config-form/sections/BaseSection.tsx
@@ -41,7 +41,6 @@ import Heading from "@/components/ui/heading";
 import get from "lodash/get";
 import cloneDeep from "lodash/cloneDeep";
 import isEqual from "lodash/isEqual";
-import merge from "lodash/merge";
 import {
   Collapsible,
   CollapsibleContent,
@@ -73,6 +72,7 @@ import {
   buildConfigDataForPath,
   flattenOverrides,
   getBaseCameraSectionValue,
+  mergeProfileOverrides,
   resolveHiddenFieldEntries,
   sanitizeSectionData as sharedSanitizeSectionData,
   requiresRestartForOverrides as sharedRequiresRestartForOverrides,
@@ -353,7 +353,10 @@ export function ConfigSection({
           `profiles.${profileName}.${sectionPath}`,
         );
         if (profileOverrides && typeof profileOverrides === "object") {
-          return merge(cloneDeep(baseValue ?? {}), cloneDeep(profileOverrides));
+          return mergeProfileOverrides(
+            (baseValue as object) ?? {},
+            profileOverrides as object,
+          );
         }
         return baseValue;
       }
diff --git a/web/src/utils/configUtil.ts b/web/src/utils/configUtil.ts
index ee33e59b7b..54de9d9ec9 100644
--- a/web/src/utils/configUtil.ts
+++ b/web/src/utils/configUtil.ts
@@ -6,7 +6,6 @@
 
 import get from "lodash/get";
 import cloneDeep from "lodash/cloneDeep";
-import merge from "lodash/merge";
 import unset from "lodash/unset";
 import isEqual from "lodash/isEqual";
 import mergeWith from "lodash/mergeWith";
@@ -92,6 +91,32 @@ export function getBaseCameraSectionValue(
   return base !== undefined ? base : get(cam, sectionPath);
 }
 
+// mergeWith customizer that replaces arrays wholesale instead of merging them
+// positionally by index. Used when the source value is meant to fully replace
+// the destination (e.g. profile overrides, section config overrides), so an
+// empty source array correctly clears the destination array.
+const replaceArraysCustomizer = (objValue: unknown, srcValue: unknown) => {
+  if (Array.isArray(objValue) || Array.isArray(srcValue)) {
+    return srcValue !== undefined ? srcValue : objValue;
+  }
+  return undefined;
+};
+
+// Merge profile overrides on top of base config values. Matches the backend's
+// deep_merge(overrides, base_data) semantics: arrays are replaced wholesale by
+// the profile's value rather than merged positionally, so an empty array in a
+// profile clears the base array instead of leaving stale entries behind.
+export function mergeProfileOverrides<T extends object>(
+  baseValue: T,
+  profileOverrides: object,
+): T {
+  return mergeWith(
+    cloneDeep(baseValue),
+    cloneDeep(profileOverrides),
+    replaceArraysCustomizer,
+  ) as T;
+}
+
 /** Sections that can appear inside a camera profile definition. */
 export const PROFILE_ELIGIBLE_SECTIONS = new Set([
   "audio",
@@ -564,9 +589,9 @@ export function prepareSectionSavePayload(opts: {
         baseValue &&
         typeof baseValue === "object"
       ) {
-        rawSectionValue = merge(
-          cloneDeep(baseValue),
-          cloneDeep(profileOverrides),
+        rawSectionValue = mergeProfileOverrides(
+          baseValue as object,
+          profileOverrides as object,
         );
       } else {
         rawSectionValue = baseValue;
@@ -675,13 +700,12 @@ const mergeSectionConfig = (
   overrides: Partial<SectionConfig> | undefined,
 ): SectionConfig =>
   mergeWith({}, base ?? {}, overrides ?? {}, (objValue, srcValue, key) => {
-    if (Array.isArray(objValue) || Array.isArray(srcValue)) {
-      return srcValue ?? objValue;
-    }
+    const arrayResult = replaceArraysCustomizer(objValue, srcValue);
+    if (arrayResult !== undefined) return arrayResult;
 
     if (key === "uiSchema") {
       if (objValue && srcValue) {
-        return merge({}, objValue, srcValue);
+        return mergeWith({}, objValue, srcValue, replaceArraysCustomizer);
       }
       return srcValue ?? objValue;
     }