diff --git a/src/codec/ffmpeg_encoder.cpp b/src/codec/ffmpeg_encoder.cpp
index 84cb4fb..4f57727 100644
--- a/src/codec/ffmpeg_encoder.cpp
+++ b/src/codec/ffmpeg_encoder.cpp
@@ -417,7 +417,15 @@ CodecResult<std::unique_ptr<Encoder>> EncoderFactory::create(const EncoderConfig
     // a fixed bitrate, and let the encoder use fewer bits on static screen
     // content and more on motion or text. The VBV max rate still caps the
     // peak so bursts cannot overflow the receiver's UDP buffers.
-    ctx->global_quality = static_cast<int>(config.crf);
+    // CRF rate control: set x264's CRF directly as a private option.
+    // FFmpeg's global_quality + AV_CODEC_FLAG_QSCALE path divides by
+    // FF_QP2LAMBDA, giving a wrong CRF value (16/118 ≈ 0.1, essentially
+    // lossless) — hence the "-qscale is ignored" warning. Setting the
+    // private "crf" option bypasses that and gives x264 the exact value.
+    const std::string crf_value = std::to_string(config.crf);
+    if (av_opt_set(ctx->priv_data, "crf", crf_value.c_str(), 0) < 0) {
+        return CodecError{"failed to set CRF quality"};
+    }
     ctx->rc_max_rate = static_cast<int64_t>(config.bitrate_kbps) * 1000;
     // VBV: one frame period of budget keeps bursts tight — a two-frame
     // buffer lets a keyframe spike beyond what a constrained link can