FAQ
TL;DR: On HD120_CID (MT2203/TC6800), 0% of tested HEVC channels output audio; “none of them work.” This FAQ explains why the sound is missing and your safest options without bricking firmware. For owners of HD120_CID DVB‑T2 boxes affected after 2022‑05‑23. [Elektroda, h999, post #20035011]
Why it matters: Poland’s DVB‑T2 transition left many imported decoders with picture but no audio; this helps you triage fast.
Quick Facts
- Device IDs: Model HD120_CID; HW V202; SW V10023_2021/03/30 17:57:38; CPU MT2203; Tuner TC6800; DVB‑T/T2/C. [Elektroda, h999, post #20034385]
- Symptom profile: HEVC H.265 picture OK, audio tracks listed, yet no sound after Polsat test channel changes. [Elektroda, h999, post #20034385]
- Audio decoding: Only MPEG‑1/2 Layer II; lacks AC‑3/E‑AC‑3/AC‑4 used in Poland’s DVB‑T2 broadcasts. [Elektroda, tomaszlonski, post #20097916]
- Firmware limit: “No new software will cause the operation of something that is not in hardware support.” [Elektroda, tomaszlonski, post #20331851]
- Practical workaround: Recordings include audio and play on a PC; use as PVR‑only. [Elektroda, h999, post #20327542]
How do I fix no sound on H.265 DVB‑T2 channels with HD120_CID?
You cannot fix it with settings. The MT2203 platform in this box lacks AC‑3/E‑AC‑3 decoding, so HEVC channels stay silent. Use a receiver that supports these audio codecs if you need live audio. Picture remains unaffected, which matches reports. [Elektroda, tomaszlonski, post #20323944]
Will a firmware update add AC‑3/E‑AC‑3/AC‑4 decoding to this decoder?
No. Codec support depends on hardware blocks in the chipset. As one expert put it, “No new software will cause the operation of something that is not in hardware support.” Updates cannot unlock missing audio hardware. [Elektroda, tomaszlonski, post #20331851]
Do different audio tracks or language options fix the silence?
No. Users tested multiple selectable audio tracks on affected HEVC channels, and none played audio. The on‑screen audio labels can appear correct, yet output remains silent. This confirms a decode capability gap, not a track selection issue. [Elektroda, h999, post #20035011]
Can changing the region in settings help restore sound?
No. This model exposes no regional profile menu. Only the interface language can change, which does not affect audio decoding. Region switching cannot enable unsupported codecs on this hardware. [Elektroda, h999, post #20109569]
Which channels still have sound on this box in Poland?
Reports show TVP1, TVP2, and TVP Info played with audio, while HEVC commercial channels did not. That contrast helped diagnose a codec mismatch rather than a reception fault. The picture quality remained flawless. [Elektroda, h999, post #20035011]
Why does Events 24 show MPEG audio yet remain silent now?
On this unit, Events 24 displayed MPEG audio but produced no sound after 2022‑05‑23. Before that date it played. The observation supports that broadcaster audio parameters changed beyond what this hardware decodes. [Elektroda, h999, post #20035011]
What hardware is inside the AliExpress DVB‑T2 HD120_CID?
Identifiers reported: Model HD120_CID; HW version V202; SW version V10023 dated 2021/03/30 17:57:38; CPU MT2203; Tuner TC6800; System DVB‑T/T2/C. These specifics help match discussion and limitations. [Elektroda, h999, post #20034385]
Is HD120_CID always the same hardware across units?
No. Under this designation, several hardware versions exist with different processors and support. As noted, “Under this designation there were several versions of this tuner for different models and sellers.” Cross‑flashing mismatched firmware will not add missing codecs. [Elektroda, tomaszlonski, post #20331851]
Is this tuner aligned with Polish/EU DVB‑T2 audio requirements?
No. It was described as “adapted to the Russian market” with only MPEG‑1/2 Layer II audio. That omits AC‑3/E‑AC‑3/AC‑4 used locally. Many AliExpress set‑top boxes do not meet Poland’s adopted standard. [Elektroda, tomaszlonski, post #20097916]
How can I confirm the broadcast actually contains audio?
Make a short recording on the box, then play the TS file on a computer. Users confirmed the recording plays with sound on PC, proving the stream carries audio that the box cannot decode. [Elektroda, h999, post #20327542]
The USB update file isn’t detected (evn1509c-115-0902_rom_all.bin). What can I try safely?
The updater did not list that file, even though USB storage was visible. That points to a filename or package format mismatch for this model. How‑To: 1. Copy the file to the USB root. 2. Open the box’s update menu. 3. If it’s not listed, stop and avoid forcing cross‑flashes. [Elektroda, h999, post #20109569]
Can I at least use HD120_CID as a recorder (PVR) and play files elsewhere?
Yes. Recordings from the box include audio and play fine on a computer. Many owners repurpose the unit as a PVR‑only device to archive shows and decode on PC software. [Elektroda, h999, post #20327542]
Is there an OEM name or board ID that helps when searching info?
One owner reported the unit as “Decoder D‑Sift 74.” A hidden screw sits under the CE lettering on the sticker; probing reveals it. Opening may expose board markings for research. [Elektroda, flinc, post #21403614]
Did anyone post a complete fix for live audio on this hardware?
No. The original poster shelved the unit awaiting a solution. No confirmed firmware or method restored live AC‑3/E‑AC‑3 output on this MT2203 model. [Elektroda, h999, post #20323604]
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