diff --git a/impl/src/config.h.template b/impl/src/config.h.template
index b9ffc23..9a14d56 100644
--- a/impl/src/config.h.template
+++ b/impl/src/config.h.template
@@ -70,4 +70,14 @@
 #define SDR_GAIN_RX_LNA   30.0f   // RF variable gain amplifier.
 #define SDR_GAIN_RX_VGA   24.0f   // Baseband variable gain amplifier.
 
+// Offset compensation (these values will be subtracted from all samples).
+// These generally depend on the gain settings above and need to be adjusted
+// when the gain is changed.
+
+#define SDR_TX_OFFSET_I  0.000000f
+#define SDR_TX_OFFSET_Q  0.000000f
+
+#define SDR_RX_OFFSET_I  0.000000f
+#define SDR_RX_OFFSET_Q  0.000000f
+
 #endif // CONFIG_H
diff --git a/impl/src/sdr/sdr_sxceiver.c b/impl/src/sdr/sdr_sxceiver.c
index 62beb16..994e963 100644
--- a/impl/src/sdr/sdr_sxceiver.c
+++ b/impl/src/sdr/sdr_sxceiver.c
@@ -198,7 +198,7 @@ result_t sdr_init(sdr_ctx_t *ctx)
 	// set up and start RX
 
 	// set gains
-	if(SoapySDRDevice_setGainElement(ctx->sdr, SOAPY_SDR_RX, 0, "PGA", SDR_GAIN_RX_PGA) != 0) {
+	/*if(SoapySDRDevice_setGainElement(ctx->sdr, SOAPY_SDR_RX, 0, "PGA", SDR_GAIN_RX_PGA) != 0) {
 		LOG(LVL_ERR, "setGainElement fail: %s", SoapySDRDevice_lastError());
 		return ERR_SOAPY;
 	}
@@ -206,6 +206,11 @@ result_t sdr_init(sdr_ctx_t *ctx)
 	if(SoapySDRDevice_setGainElement(ctx->sdr, SOAPY_SDR_RX, 0, "LNA", SDR_GAIN_RX_LNA) != 0) {
 		LOG(LVL_ERR, "setGainElement fail: %s", SoapySDRDevice_lastError());
 		return ERR_SOAPY;
+	}*/
+
+	if(SoapySDRDevice_setGain(ctx->sdr, SOAPY_SDR_RX, 0, SDR_GAIN_RX) != 0) {
+		LOG(LVL_ERR, "setGain fail: %s", SoapySDRDevice_lastError());
+		return ERR_SOAPY;
 	}
 
 	if(SoapySDRDevice_activateStream(ctx->sdr, ctx->rx_stream, 0, 0, 0) != 0) {
@@ -292,15 +297,38 @@ result_t sdr_transmit(sdr_ctx_t *ctx, const float complex *samples, size_t nsamp
 		flags |= SOAPY_SDR_HAS_TIME;
 	}
 
-	void *buffs[] = {(void*)(samples)};
+	const size_t BLOCK_SIZE = 4096;
+	float complex tx_block[BLOCK_SIZE];
 
-	int ret = SoapySDRDevice_writeStream(ctx->sdr, ctx->tx_stream, (const void* const*)buffs, nsamples, &flags, time_ns, timeout_us);
+	size_t samples_transmitted = 0;
 
-	if(ret <= 0) {
-		LOG(LVL_ERR, "writeStream fail: %s", SoapySDRDevice_lastError());
-		return ERR_SOAPY;
-	} else if(ret != nsamples) {
-		LOG(LVL_WARN, "writeStream() did not transmit all samples: %i/%zu", ret, nsamples);
+	while(samples_transmitted < nsamples) {
+		size_t samples_remaining = nsamples - samples_transmitted;
+		size_t block_samples = BLOCK_SIZE;
+
+		if(samples_remaining < BLOCK_SIZE) {
+			block_samples = samples_remaining;
+		}
+
+		const float complex *block_start = samples + samples_transmitted;
+		for(size_t i = 0; i < block_samples; i++) {
+			tx_block[i] = block_start[i] - (SDR_TX_OFFSET_I + I * SDR_TX_OFFSET_Q);
+		}
+
+		void *buffs[] = {(void*)(tx_block)};
+
+		int64_t block_time = time_ns + samples_transmitted * 1000000000LL / SDR_TX_SAMPLING_RATE;
+
+		int ret = SoapySDRDevice_writeStream(ctx->sdr, ctx->tx_stream, (const void* const*)buffs, block_samples, &flags, block_time, timeout_us);
+
+		if(ret <= 0) {
+			LOG(LVL_ERR, "writeStream fail: %s", SoapySDRDevice_lastError());
+			return ERR_SOAPY;
+		} else if((size_t)ret != block_samples) {
+			LOG(LVL_WARN, "writeStream() did not transmit all samples: %i/%zu", ret, block_samples);
+		}
+
+		samples_transmitted += ret;
 	}
 
 	return OK;
@@ -313,18 +341,41 @@ result_t sdr_receive(sdr_ctx_t *ctx, float complex *samples, size_t *nsamples, l
 		return ERR_INVALID_STATE;
 	}
 
-	void *buffs[] = {(void*)samples};
+	const size_t BLOCK_SIZE = 4096;
+	float complex rx_block[BLOCK_SIZE];
 
-	long long timeNs;
-	int flags;
-	int ret = SoapySDRDevice_readStream(ctx->sdr, ctx->rx_stream, (void* const*)buffs, *nsamples, &flags, &timeNs, timeout_us);
+	size_t samples_received = 0;
 
-	if(ret <= 0) {
-		LOG(LVL_ERR, "readStream fail: %s", SoapySDRDevice_lastError());
-		return ERR_SOAPY;
+	while(samples_received < *nsamples) {
+		size_t samples_remaining = *nsamples - samples_received;
+		size_t block_samples = BLOCK_SIZE;
+
+		if(samples_remaining < BLOCK_SIZE) {
+			block_samples = samples_remaining;
+		}
+
+		void *buffs[] = {(void*)(rx_block)};
+
+		long long timeNs;
+		int flags;
+		int ret = SoapySDRDevice_readStream(ctx->sdr, ctx->rx_stream, (void* const*)buffs, block_samples, &flags, &timeNs, timeout_us);
+
+		if(ret <= 0) {
+			LOG(LVL_ERR, "readStream fail: %s", SoapySDRDevice_lastError());
+			return ERR_SOAPY;
+		} else if((size_t)ret != *nsamples) {
+			LOG(LVL_WARN, "readStream() did not receive all requested samples: %i/%zu", ret, block_samples);
+		}
+
+		float complex *block_start = samples + samples_received;
+		for(size_t i = 0; i < (size_t)ret; i++) {
+			block_start[i] = rx_block[i] - (SDR_RX_OFFSET_I + I * SDR_RX_OFFSET_Q);
+		}
+
+		samples_received += ret;
 	}
 
-	*nsamples = ret;
+	*nsamples = samples_received;
 
 	return OK;
 }