diff --git a/runtime/src/main.cpp b/runtime/src/main.cpp
index ab4ff798..38cf26fc 100644
--- a/runtime/src/main.cpp
+++ b/runtime/src/main.cpp
@@ -10661,8 +10661,8 @@ namespace {
 
 int main(int argc, char** argv) {
     /* Force line-buffered output so messages appear even if killed. */
-    std::setvbuf(stdout, nullptr, _IOLBF, 0);
-    std::setvbuf(stderr, nullptr, _IOLBF, 0);
+    std::setvbuf(stdout, nullptr, _IOLBF, BUFSIZ);
+    std::setvbuf(stderr, nullptr, _IOLBF, BUFSIZ);
     std::fprintf(stderr, "psxrecomp: main() entered\n");
     std::fflush(stderr);
 #if defined(RECOMP_LAUNCHER)