diff --git a/src/device/controller.ts b/src/device/controller.ts
index 7ce0bbf8..4a4f19b3 100644
--- a/src/device/controller.ts
+++ b/src/device/controller.ts
@@ -253,9 +253,10 @@ export const PULSAR_SLEEP_OPTIONS: ReadonlyArray<readonly [number, string]> = [
 const BACKGROUND = "Background refresh";
 const FLASH_STEP_DELAY_MS = 420;
 const FLASH_SETTLE_MS = 320;
-// Longest a flash waits for an in-flight device refresh before giving up
-// instead of busy-waiting forever.
-const REFRESH_WAIT_TIMEOUT_MS = 2000;
+// Longest a flash waits for an in-flight device read before giving up
+// instead of busy-waiting forever. A full onboard-profile reread over a
+// wireless link can take a few seconds.
+const REFRESH_WAIT_TIMEOUT_MS = 5000;
 
 const previewModeEnabled = previewsEnabled(__BUILD_CHANNEL__, import.meta.env.DEV);
 const previewMode = previewModeEnabled
@@ -357,6 +358,8 @@ const napeKeymaps = new Map<number, KeychronNapeLayerKeymap>();
 const stagedNapeAssignments = new Map<string, StagedNapeAssignment>();
 let keymapReadToken = 0;
 let onboardProfilesLoading = false;
+// A status applied mid-write skips the profile read; the write's end retries it.
+let onboardReloadDeferred = false;
 let lastDeviceMode: MouseStatus["deviceMode"] = "Unknown";
 let lastProfileFormat: MouseStatus["onboardProfileFormat"] = null;
 
@@ -2192,13 +2195,17 @@ export async function flashPendingChanges(): Promise<void> {
   emit();
   let written = 0;
   let failure: string | null = null;
-  if (refreshInProgress) {
+  // HID++ replies are matched by feature and function only, so a profile read
+  // still running in the background would take the write's sector reads and
+  // fail its checksum check. Let every read finish first.
+  const reading = (): boolean => refreshInProgress || onboardProfilesLoading;
+  if (reading()) {
     pendingStatusText = st("ctl.waitRefresh");
     readStatus = pendingStatusText;
     emit();
     const refreshDeadline = Date.now() + REFRESH_WAIT_TIMEOUT_MS;
-    while (refreshInProgress && Date.now() <= refreshDeadline) await wait(25);
-    if (refreshInProgress) {
+    while (reading() && Date.now() <= refreshDeadline) await wait(25);
+    if (reading()) {
       const timeout = new Error("Timed out waiting for the device refresh.");
       recordDiagnosticError(timeout, st("ctl.unableFlash"));
       failure = timeout.message;
@@ -2248,8 +2255,11 @@ export async function flashPendingChanges(): Promise<void> {
 
 function endDeviceWrite(): void {
   settingInProgress = false;
+  const retryProfiles = onboardReloadDeferred && onboardProfiles === null && !onboardProfilesLoading;
+  onboardReloadDeferred = false;
   syncProfileDerivedState();
   emit();
+  if (retryProfiles) void reloadOnboardProfiles();
 }
 
 function saveInterfacePreferences(): void {
@@ -2697,7 +2707,10 @@ function applyStatusInner(deviceStatus: MouseStatus, statusKey?: string): void {
   if (supportsOnboard) {
     lastDeviceMode = status.deviceMode;
     lastProfileFormat = status.onboardProfileFormat ?? null;
-    if (onboardProfiles === null && !onboardProfilesLoading) void reloadOnboardProfiles();
+    // A read started mid-write would interleave with the write's sector reads,
+    // so it waits for endDeviceWrite().
+    if (onboardProfiles === null && !onboardProfilesLoading && settingInProgress) onboardReloadDeferred = true;
+    if (onboardProfiles === null && !onboardProfilesLoading && !settingInProgress) void reloadOnboardProfiles();
     else syncProfileDerivedState();
   }
   syncEditedNapeLayer(deviceStatus);
@@ -4696,6 +4709,12 @@ export function describeProfileEntry(entry: OnboardProfile | null): { name: stri
   };
 }
 
+/** The reload button. Skipped mid-write, which rereads the profiles itself. */
+export function rereadOnboardProfiles(): void {
+  if (settingInProgress) return;
+  void reloadOnboardProfiles();
+}
+
 export async function reloadOnboardProfiles(): Promise<boolean> {
   const client = logitechClient();
   if (!client || onboardProfilesLoading) return false;
diff --git a/src/features/profiles/Profiles.tsx b/src/features/profiles/Profiles.tsx
index e081e92f..278c1cc8 100644
--- a/src/features/profiles/Profiles.tsx
+++ b/src/features/profiles/Profiles.tsx
@@ -84,7 +84,7 @@ export function Profiles({
           type="button"
           aria-label={t(locale, "prof.reload")}
           title={t(locale, "prof.reload")}
-          onClick={() => void control.reloadOnboardProfiles()}
+          onClick={() => control.rereadOnboardProfiles()}
         >
           <IconRefresh />
         </button>