The Sony Xperia Z5 Premium is the most powerful among the Z5 devices. The handset was launched alongside the Xperia Z5 Compact and regular Xperia Z5. A side-mounted fingerprint scanner is on all three devices, but some Xperia Z5 Premium handsets are facing problems.

It is not yet clear whether or not this fingerprint scanner issue is widespread, but we've seen a video discussing the feature's situation.

The problem some users are facing with the fingerprint scanner, is the inability to unlock a device at times. PocketNow reported a 50 percent success rate in unlocking the Xperia Z5 Premium with the scanner. The publication also went on to state that the rate can be as low as two times out of 10.

Based on the video, the fingerprint scanner seems so unreliable that it just didn't make sense at times to have the feature activated. For a time, registered fingerprints seem to work just fine, then for some odd reason, the device refuses to recognize them.

Such a problem might cause frustration among Z5 Premium owners who want to use their fingerprint scanner, and Sony must do whatever to get the issue under control before it spreads. For now, it is difficult to tell if this is a huge problem among consumers, but checking Sony's blog and Twitter accounts, there are customers who are already complaining about the same problems.

Chances are the issue could either be a hardware or software problems. If ever it is a software anomaly, a simple update would definitely get it under control. However, if it is a problem with the hardware, then Sony may have to recall several Xperia Z5 Premium handsets in the near future, but that is only if the problem escalates.

So far, Sony has not made a statement regarding the fingerprint scanner issue on the Z5 Premium, but we are expecting something from the Japanese company soon.

For the meantime, the video suggested an extra step to somehow make the fingerprint scanner work better. "[T]he scanner needs to be clean. Take this in a strict way. Not talking about thick grease or dirt, we’re talking about previous fingerprints from a single touch that can render it unusable."

But don't expect the step to work while using the phone underwater or if you have wet, or even moist, fingers or phone.

The video below shows the fingerprint scanner problem on the Z5 Premium.

Photo: Masaru Suzuki | Flickr