xrootdatetime: fixing crash on initial boot

xrootdatetime: trying to fix crashes
xrootdatetime: allow errors

modules/dwm.nix

@@ -44,15 +44,25 @@ in
     };
 
     systemd.user.services.xrootdatetime = {
-      script = ''
+      script =
+        let
+          pamixer = getExe pkgs.pamixer;
+          xsetroot = getExe pkgs.xorg.xsetroot;
+        in
+          /* bash */ ''
           while true; do
-          if [[ "$(${getExe pkgs.pamixer} --default-source --get-mute)" == "true" ]]; then
+            set +e # allow errors
+            mute="$(${pamixer} --default-source --get-mute)"
+            set -e # disallow errors
+
+            if [[ "$mute" == "true" ]]; then
               mutedString="Mic Muted "
             else
               mutedString=""
             fi
+
             dateTime=$(date +"<-- %A, %B %d -- %H:%M -->")
-          ${getExe pkgs.xorg.xsetroot} -name "$mutedString$dateTime"
+            ${xsetroot} -name "$mutedString$dateTime"
             sleep 1
           done
         '';