That’s all well and good. A music file is not just a music file.
But a device that is built for one specific purpose must run firmware whose top priority is to maintain the absolute basic functions (the music seems to keep playing, but the GUI becomes more and more unusable).
This firmware also needs to be capable of handling exotic or corrupted files, timeouts to a streaming service, and other edge cases. Memory leaks indicate that such scenarios were either not taken into account or not tested sufficiently.
From what I’ve understood, these problems didn’t exist in the past and only appeared with a later update (4.4.x?).
I currently own an XDJ‑AZ myself and I’m considering switching to the Prime 4+ because of the stems. But as long as users keep reporting memory leaks, I’m certainly not putting two grand on the table.
I wrote at the beginning that I have a new, clean library. My music files processed by mp3tag contain only the title and artist, no cover art. The cover art is simply placed in the Engine Library folder, as Denon recommends.
I’ll tell you that I’ve had it for over a year when the 4.0.0 update came out and only after some time I started noticing these performance drops and stutters, previously I thought it was supposed to be like that.
From what I have seen using the service overlay there is a clear lack of RAM in these units. I get glitches when loading the second deck on the Prime Go plus so I can only imagine it would be worse on a 4 channel unit.
Using the lighting module (introduced far later) eats even more RAM which is not the way these players were designed.
The platform is seriously out of date and even the two plus versions are operating on ancient and under spec hardware.
I was contacted about joining the beta team to test new firmware to see if this has improved but the person who messaged me hasn’t replied since I filled in the application form quite some time ago.
Its becoming a joke for supposedly professional equipment.
I’ve had the Prime 4+ Since August 2025 from new, running the latest firmware, and just wanted to pipe in that I also have this issue. I’ve used it a lot since I bought it and I’ve tried to self diagnose it myself. The unit will be fine when you first boot it, but after maybe 2 or so hours it starts to slow down as time progresses and can get reeealy slow if you have it on for like 8 or so hours.
Initially I thought it was my storage, but I’ve replaced it with a very quick Crucial SSD that’s far in excess of what should really be needed to play music. I have around 12k songs on the SSD and it’s sitting below 200GB in storage used. The library has been exported straight from the latest version of Engine DJ Desktop. I’ve ran my library through mp3tag and removed any strange characters from the metadata and have downsized the artwork of all my songs to a very low size.
I also use TIDAL streaming on the unit alongside my local library. I’ve had nights where I’ve used exclusively Tidal and exclusively my local library and the issue seems to happen no matter where the music is coming from.
When it starts to slow down it becomes very difficult to actually use the unit, especially if you’re an open-format DJ like I am and constantly need to sort through playlists and search for songs. The waveforms start to lag, and sometimes if you trigger a loop it can just freeze the waveforms entirely for a few seconds. If you switch between Tidal and local storage it can take a long time to do anything.
I honestly do not believe that this is caused by the unit getting too hot. At one of my gigs, I play alongside a band. When the band are on, if I restart the unit it immediately goes back to normal and it takes another few hours for it to start slowing down again.
I love the unit (I own an RX3 too and the Prime4+ does blow it out of the water when it’s working properly. the RX3 is also tremendously buggy and just freezes sometimes) but I’ve also had issues with build quality (the paint is starting to come off the unit already…) and in general I don’t think I could trust the unit at a gig where I would need to play for a prolonged period of time.
The whole reason I bought the unit was because it is advertised as an all in one. I shouldn’t have to rely on a backup source of music to restart it to make it usable again. I suspect it’s poor memory/ram management. either that or there’s an issue with the CPU in these units but I doubt it. I think the latest firmware has improved the situation slightly but there’s still a problem somewhere.
I have a few more tags, and my album art is embedded in the tags.
One possibility is that the track is longer.
Unfortunately, there are hardly any real extended versions like in the old days, which were around 7 minutes long.
These days, a normal song is often under 3 minutes, and the extended version is then only 30 seconds longer—what a joke.
Have you perhaps played any extremely long tracks?
Come to think of it, I’ve never given the P4 anything longer Tracks than 11 minutes.
Like I said, just thinking out loud.
The fact is, the device simply has to work.
I had the “AZ” alongside my Prime 2 for six weeks.
After three gigs, during which the device completely crashed on the third, I returned it to the music store and bought the P4+.
It’s been working well so far, but I only use it in standalone mode every two to three gigs.
VDJ is often a useful alternative for me.
Unfortunately, I’m running out of other ideas, since several people have now confirmed the problem you’re experiencing, and that doesn’t exactly inspire confidence.
Can we expect any comments from Denon Representatives? I thought this forum was for two-way communication. We can all see that this is not a problem affecting just one user, but many people. I would like to know if an investigation is underway and what remedial measures are planned.
Apparently there’s a new firmware that may solve the issues. I was contacted by a beta representative but rejected because I already beta test for another platform. Sort of ironic as I thought they’d encourage experienced beta testers but hey ho …..
Hello. I’ve been having problems with my P4+ for a while now, specifically with the system and the screen itself after about 4 hours of use. The screen lags terribly, terribly. Quickly entering a song title in the search bar is practically impossible. Changing menu options or browsing directories is very slow. When changing the BPM, the “waveform width” should change, but it only does so after a while of playing the song or after fast-forwarding. I’d also like to point out that the sound itself and the “button” functions work without any problems. I play at various events, clubs, and special occasions, so I use the “Denon Lightning” lighting controller when I’m not at the club, and it doesn’t affect the device’s performance. First, I’m considering installing an older version of the software…
I tried 4.2.0 last night and had exactly the same issues. Tracks pausing when loading the other deck. Happened probably 10 times in a 5 hour gig so rolling back isn’t a solution.
ja też testowałem inne wersje i wróciłem do 4.2 bo działa najbardziej stabilnie. Wiadomo do ideału daleko. Pograsz 2- 3 godziny i widocznie spowalnia ale jakoś działa. No i jest jeszcze jedna rzecz w 4.2 a mianowicie nie ładuje folderu Steam, pokazuje informację update ale to wszystko , zawartości folderu nie ładuje.
Też wielokrotnie pisałem do supportu i dostawałem różne sugestie np. słaby dysk , żele sformatowany i tak dalej … sami wiecie jak odpisują . Nawet na małej playliście sprawdzałem z 2 - 3 giga muzyki. To samo…..
that was already a few months ago.
