diff --git a/patch_v2/meow_watchdog/meow_watchdog b/patch_v2/meow_watchdog/meow_watchdog
index 96566b5..54a00b6 100755
Binary files a/patch_v2/meow_watchdog/meow_watchdog and b/patch_v2/meow_watchdog/meow_watchdog differ
diff --git a/patch_v2/meow_watchdog/meow_watchdog.c b/patch_v2/meow_watchdog/meow_watchdog.c
index d2a1b57..104bc49 100644
--- a/patch_v2/meow_watchdog/meow_watchdog.c
+++ b/patch_v2/meow_watchdog/meow_watchdog.c
@@ -367,17 +367,38 @@ static void wd_vol_write(int pct)
     wd_log("DAC vol -> L/R=%d (pct %d)", dac, pct);
 }
 
+/* M2.92+ 修复（真机实证 settings.conf 被毁）：旧版 O_TRUNC 整文件重写只剩 4 行 ——
+ * 抹掉全部其它设置；与其它写者交错还叠出重复 audio.volume 行、丢 volume_max/step。
+ * 改为读改写单键（流式拷贝、命中行全部改写去重、缺失末尾追加、rename 原子替换），
+ * 与 SDK meow_ui_vol_set 同款语义。 */
 static void wd_vol_save(void)
 {
     system("mkdir -p /usr/data/meow 2>/dev/null");
-    int fd = open(MEOW_SETTINGS_FILE, O_WRONLY | O_CREAT | O_TRUNC, 0644);
-    if (fd < 0) { wd_log("vol: open %s fail: %s", MEOW_SETTINGS_FILE, strerror(errno)); return; }
-    char buf[128];
-    int l = snprintf(buf, sizeof buf,
-        "# meow-settings 1\naudio.volume = %d\naudio.volume_max = %d\naudio.volume_step = %d\n",
-        wd_vol, wd_vol_max, wd_vol_step);
-    if (write(fd, buf, l) < 0) wd_log("vol: write fail: %s", strerror(errno));
-    close(fd);
+    const char *path = MEOW_SETTINGS_FILE;
+    char tmp[300];
+    snprintf(tmp, sizeof tmp, "%s.tmp", path);
+    FILE *in = fopen(path, "r");
+    FILE *out = fopen(tmp, "w");
+    if (!out) { if (in) fclose(in); wd_log("vol: save open tmp fail"); return; }
+    int found = 0;
+    char line[256];
+    while (in && fgets(line, sizeof line, in)) {
+        char *eq = strchr(line, '=');
+        char *k = line;
+        while (*k == ' ' || *k == '\t') k++;
+        int n = eq ? (int)(eq - k) : 0;
+        while (n > 0 && (k[n-1] == ' ' || k[n-1] == '\t')) n--;
+        if (eq && n == 12 && strncmp(k, "audio.volume", 12) == 0) {
+            if (!found) fprintf(out, "audio.volume = %d\n", wd_vol);   /* 命中：只写一次（去重） */
+            found = 1;
+        } else {
+            fputs(line, out);
+        }
+    }
+    if (in) fclose(in);
+    if (!found) fprintf(out, "audio.volume = %d\n", wd_vol);
+    fclose(out);
+    if (rename(tmp, path) != 0) { remove(tmp); wd_log("vol: save rename fail"); return; }
     wd_log("vol: saved volume=%d(max=%d,step=%d)", wd_vol, wd_vol_max, wd_vol_step);
 }
 
diff --git a/patch_v2/meow_watchdog/test_wd_fw b/patch_v2/meow_watchdog/test_wd_fw
index 30b1939..4da5ce5 100755
Binary files a/patch_v2/meow_watchdog/test_wd_fw and b/patch_v2/meow_watchdog/test_wd_fw differ
diff --git a/scripts/build/fw_content.conf b/scripts/build/fw_content.conf
index 904b1aa..fb9360b 100644
--- a/scripts/build/fw_content.conf
+++ b/scripts/build/fw_content.conf
@@ -29,7 +29,7 @@
 # ---- 用户态/服务守护二进制（usr/bin，全部 chmod 755 静态 MIPS）----
 patch_v2/bootmenu/meow_bootmenu|/usr/bin/meow_bootmenu|4441822d87e76bfce2ce584604ac3830|引导选单 M2.85（sysui让位 agent-216）
 patch_v2/meow_launcherd/meow_launcherd|/usr/bin/meow_launcherd|6de9762881245a57f547d53102e996be|主屏 launcher M2.92（NP页死循环/电源键/自动息屏修复+充电闪电图标+255插孔消抖并入）
-patch_v2/meow_watchdog/meow_watchdog|/usr/bin/meow_watchdog|baa997ea9100b04e1cc96e25c16f7e4b|应用看门狗（插孔消抖：插拔瞬态忽略音量键 800ms；M2.89 SIGUSR1 仅裸沉浸 App）
+patch_v2/meow_watchdog/meow_watchdog|/usr/bin/meow_watchdog|52f2dadd6e14a571bb60f48582a2ba66|应用看门狗 M2.93（+wd_vol_save 不再 O_TRUNC 毁设置文件, 改读改写单键去重）
 patch_v2/meow_svcd/meow_svcd|/usr/bin/meow_svcd|605646c4cc93f2baf29071ea6bc870ea|服务管理器 M2.77（+崩溃上报 meow_crash agent-187）
 mips-repo/bins/meow_mdns/bin/meow_mdns|/usr/bin/meow_mdns|d6b0151bda26768f19952dae1342610d|mDNS 应答器 M2.78（启动竞态+换IP重检 agent-194）
 patch_v2/meow_sysui/meow_sysui|/usr/bin/meow_sysui|173013cc8f0899b3001d0b894ac0d9e6|系统 UI（sysui）