diff --git a/mmclab/example/demo_example_replay.m b/mmclab/example/demo_example_replay.m
index e7ef49d..1909290 100644
--- a/mmclab/example/demo_example_replay.m
+++ b/mmclab/example/demo_example_replay.m
@@ -36,6 +36,7 @@
 cfg.issaveexit = 1;  % save detected photon exit position and angles
 cfg.issaveseed = 1;  % save detected photon seeds to replay later
 % cfg.method=0;
+cfg.compute='cuda';
 
 newcfg = mmclab(cfg, 'prep');  % preprocessing of the mesh to get the missing fields
 
diff --git a/src/mmc_core.cl b/src/mmc_core.cl
index 764c8ca..7dbf0df 100644
--- a/src/mmc_core.cl
+++ b/src/mmc_core.cl
@@ -1455,6 +1455,10 @@ __device__ void onephoton(unsigned int id, __local float* ppath, __constant MCXP
     RandType initseed[RAND_BUF_LEN];
 #endif
 
+    clearpath(ppath, (GPU_PARAM(gcfg, reclen) + (GPU_PARAM(gcfg, srcnum) > 1) * GPU_PARAM(gcfg, srcnum)));
+    clearpath(energytot, GPU_PARAM(gcfg, srcnum));
+    clearpath(energyesc, GPU_PARAM(gcfg, srcnum));
+
     r.photonid = id;
 
 #ifdef MCX_SAVE_SEED
@@ -1734,9 +1738,6 @@ __kernel void mmc_main_loop(const int nphoton, const int ophoton,
         gpu_rng_init(t, n_seed, idx);
     }
 
-    clearpath(sharedmem, get_local_size(0) * ((GPU_PARAM(gcfg, srcnum) << 1) +
-              (GPU_PARAM(gcfg, reclen) + (GPU_PARAM(gcfg, srcnum) > 1) * GPU_PARAM(gcfg, srcnum))));
-
     /*launch photons*/
     for (int i = 0; i < nphoton + (idx < ophoton); i++) {
         if (GPU_PARAM(gcfg, seed) == SEED_FROM_FILE)