diff --git a/artiq/coredevice/comm_kernel.py b/artiq/coredevice/comm_kernel.py
index 2d529b6f9..930430b5e 100644
--- a/artiq/coredevice/comm_kernel.py
+++ b/artiq/coredevice/comm_kernel.py
@@ -418,6 +418,9 @@ class CommKernel:
             self._skip_rpc_value(tags)
         elif tag == "r":
             self._skip_rpc_value(tags)
+        elif tag == "a":
+            _ndims = tags.pop(0)
+            self._skip_rpc_value(tags)
         else:
             pass