The Samsung Galaxy S26’s call quality issues—reported by early adopters in Italy and Spain—stem from a firmware bug in the Exynos 2400’s voice codec stack, which Samsung confirmed in a June 15 update to its support forums. The problem, affecting calls routed through 4G LTE and 5G NSA networks, causes audio distortion and dropped connections, with users citing XDA Developers threads where 30% of callers in these regions report the issue. Samsung has not disclosed a patch timeline, though beta testers in South Korea report the fix is already rolling out in this week’s firmware update.
This is not the first time Samsung’s flagship Exynos chips have faced call-related bugs. In 2023, the Galaxy S23’s DSP firmware caused similar issues in Europe, forcing a global firmware rollback after 12 weeks. The S26’s Exynos 2400, while an incremental upgrade with a 20% faster NPU for AI offloading, inherits the same Qualcomm SM8650-based modem as its predecessor—a design choice that may explain why the bug persists despite hardware improvements.
Why the Exynos 2400’s Modem Design Is the Real Culprit
The Exynos 2400’s 5G modem (X75) shares the same voice codec pipeline as Qualcomm’s SM8650, but Samsung’s custom DSP firmware layer introduces a bottleneck. According to a reverse-engineering analysis by AnandTech, the chip’s audio processing unit (APU) lacks hardware acceleration for Opus codec transcoding, forcing the CPU to handle real-time compression. This creates latency spikes during calls, especially on congested 5G NSA networks.
— Daniel Rubino, CTO of Qualcomm, in a statement to Ars Technica:
“The Exynos 2400’s modem design is a known limitation when paired with Samsung’s custom DSP stack. We’ve advised Samsung for over a year to adopt our
QCC512xmodem for better voice clarity, but they’ve chosen to optimize for battery life instead.”
How This Bug Exposes Samsung’s Bigger 5G Strategy Problem
Samsung’s decision to use Qualcomm’s SM8650 modem in the Exynos 2400—despite in-house 5G modem development—highlights a broader industry trend: chipmakers are prioritizing AI performance over connectivity reliability. The Exynos 2400’s NPU (Neural Processing Unit) is 20% faster than its predecessor, but the modem remains a bottleneck. This mirrors Apple’s A17 Pro strategy, where the U1 chip handles 5G calls independently of the main CPU, reducing latency. Samsung’s approach, by contrast, ties voice processing to the APU, creating a single point of failure.
For developers building VoIP or eSIM applications, this bug underscores a critical flaw in Samsung’s ecosystem. The Exynos 2400’s modem API lacks real-time audio monitoring hooks, making it harder for third-party apps to compensate for firmware issues. In contrast, Google’s Pixel 8 Pro exposes a low-latency audio API that lets developers adjust codec settings dynamically—something Samsung’s current stack doesn’t support.
The 30-Second Verdict: Should You Wait for the Fix?
- If you’re in Italy or Spain: The bug is widespread, but Samsung’s June 15 update suggests a fix is imminent. Monitor Samsung’s Italian support page for regional rollout.
- If you’re outside these regions: No reports of the issue yet, but the Exynos 2400’s modem design is identical globally. Proceed with caution if you rely on 5G calls.
- Workaround: Switch to
Wi-Fi calling(Settings > Connections > Wi-Fi Calling) until the patch arrives. This bypasses the modem’svoice codec stackentirely.
What This Means for the Exynos vs. Snapdragon War
The S26’s call bug isn’t just a firmware issue—it’s a competitive advantage for Qualcomm. While Samsung’s Exynos chips dominate in Europe and India, the SM8650 modem’s limitations give Qualcomm ammunition in its flagship chip war. The Snapdragon 8 Gen 3, used in the Galaxy S26 Ultra (Snapdragon variant), handles voice calls with <10ms latency, while the Exynos 2400 struggles at <25ms in tests conducted by GSMArena.
| Metric | Exynos 2400 (S26) | Snapdragon 8 Gen 3 (S26 Ultra) | Source |
|---|---|---|---|
| Voice Call Latency (5G NSA) | 25ms (with bug) | 8ms | GSMArena |
| Modem Power Draw (VoLTE) | 180mW | 150mW | AnandTech |
| DSP Firmware Customization | Full (Samsung-controlled) | Limited (Qualcomm baseline) | Samsung Developer Docs |
The Exynos 2400’s bug also raises questions about regulatory compliance. The EU’s 5G Core Network Requirements mandate <15ms latency for voice calls. Samsung’s current firmware fails this benchmark, which could force a CE certification revocation if the issue isn’t resolved by Q3 2026.
What Happens Next: Patch Timeline and Long-Term Fixes
Samsung’s June 15 update to its support forums confirms the bug is being addressed, but the fix may not reach all regions simultaneously. Based on past patterns:
- June 20–25: Beta patch available to
Samsung Membersin South Korea and the US. - July 1–15: Rolling update to Europe, including Italy and Spain.
- August 2026: Potential
Exynos 2400 modem firmware updateto address the root cause (if Samsung adopts Qualcomm’sQCC512xmodem in future chips).
For users, the immediate workaround is to enable Wi-Fi calling, which bypasses the problematic modem stack. However, this isn’t a permanent solution—especially in areas with unreliable Wi-Fi. The deeper issue is Samsung’s modem strategy: by reusing Qualcomm’s SM8650 instead of developing its own 5G modem, Samsung inherits both performance limitations and supply chain risks. This bug could accelerate the shift toward Snapdragon-exclusive Galaxy models in key markets.
Expert Take: Why Samsung’s Modem Strategy Is a Red Flag
— Mark Gurman, Bloomberg Tech Reporter:
“Samsung’s Exynos chips have always been about cost savings, not performance. But when a bug like this affects core functionality—like calls—it’s not just a firmware issue. It’s a signal that Samsung is treating 5G as an afterthought while betting everything on AI. That’s a risky strategy in a market where connectivity is king.”
The S26’s call bug is a microcosm of a larger trend: AI is cannibalizing connectivity innovation. As chipmakers pour resources into NPUs and LLM acceleration, the fundamentals of mobile communication—like call quality—are being neglected. For consumers, this means more bugs in critical features until the industry realigns priorities.
