diff --git a/xwords4/common/comms.c b/xwords4/common/comms.c
index b80172b14..52c975c8d 100644
--- a/xwords4/common/comms.c
+++ b/xwords4/common/comms.c
@@ -417,7 +417,7 @@ comms_make( MPFORMAL XWEnv xwe, XW_UtilCtxt* util, XP_Bool isServer,
             XP_U16 forceChannel )
 {
     CommsCtxt* comms = (CommsCtxt*)XP_CALLOC( mpool, sizeof(*comms) );
-    MUTEX_INIT( &comms->mutex, XP_TRUE );
+    MUTEX_INIT_CHECKED( &comms->mutex, XP_TRUE, 3 );
     comms->util = util;
     comms->dutil = util_getDevUtilCtxt( util, xwe );
 #ifdef DEBUG
diff --git a/xwords4/common/xwmutex.c b/xwords4/common/xwmutex.c
index 38ce2329d..26c65fce2 100644
--- a/xwords4/common/xwmutex.c
+++ b/xwords4/common/xwmutex.c
@@ -22,7 +22,13 @@
 #ifdef DEBUG
 #include <unistd.h>
 
-#define WAIT_ALL_SECS 3
+// #define WAIT_ALL_SECS 3
+/* #define WAIT_ALL_SECS to enable checking for ALL mutexes, but don't do that
+    on Android because it kills the app (because locks in mpool are so
+    frequent, I suspect). I'll keep it on on Linux for testing, but even there
+    it limits how many games I can run at once. I really need a cleverer
+    implementation where a single thread checks everything....
+*/
 
 /* What is this? It's my attempt to, on debug builds and for all or only
    chosen mutexes, get an assertion when the app doesn't get a lock in the
@@ -95,9 +101,9 @@ mtx_lock_prv( MutexState* state, XP_U16 waitSecs,
         (void)pthread_create( &waitThread, NULL, checkLockProc, &ws );
         int count = 0;
         while ( !ws.flagLoc ) {
-            usleep(50); /* wait for thread to start */
+            usleep(500); /* wait for thread to start */
             if ( 0 == (++count%10) ) {
-                XP_LOGFF( "count %d; flagLoc still null", count );
+                // XP_LOGFF( "count %d; flagLoc still null", count );
             }
         }
     }
diff --git a/xwords4/linux/Makefile b/xwords4/linux/Makefile
index 028976756..7bdb8f9a4 100644
--- a/xwords4/linux/Makefile
+++ b/xwords4/linux/Makefile
@@ -19,7 +19,8 @@
 BUILD_DIR ?= .
 
 ifeq ($(MEMDEBUG),TRUE)
-DEFINES = -DMEM_DEBUG -DDEBUG -DENABLE_LOGGING -DNUMBER_KEY_AS_INDEX 
+DEFINES = -DMEM_DEBUG -DDEBUG -DENABLE_LOGGING -DNUMBER_KEY_AS_INDEX
+DEFINES += -DWAIT_ALL_SECS=3
 DEFINES += -DLOG_COMMS_MSGNOS
 DEFINES += -DDI_DEBUG
 CFLAGS += -g $(GPROFFLAG) -Wall -Wunused-parameter -Wcast-align -Werror -O0