diff --git a/libspark/record_lib.h b/libspark/record_lib.h
index 15fc87b..5ff453e 100644
--- a/libspark/record_lib.h
+++ b/libspark/record_lib.h
@@ -39,7 +39,7 @@ class cRecord
 		unsigned char *io_buf[RECORD_WRITER_CHUNKS];
 		size_t io_len[RECORD_WRITER_CHUNKS];
 	public:
-		cRecord(int num = 0, int bs_dmx = 100 * 188 * 1024, int bs = 100 * 188 * 1024);
+		cRecord(int num = 0, int bs_dmx = 2048 * 1024, int bs = 4096 * 1024); 
 		void setFailureCallback(void (*f)(void *), void *d) { failureCallback = f; failureData = d; }
 		~cRecord();