Filming with an S24 Ultra and problems with the external microphone

[Piet9]

I use a Samsung S24 Ultra to film the figure skating competitions of my daughter and some friends.
I have been doing this for some time and have systematically bought myself a few extras.
I no longer use the standard program but rather Filmic Pro.
Beyond the normal qualities of this app, there are some nice extras.
For example, you can play the sound of the recording during recording,
this is quite useful because then you immediately know if the sound of the recording is good.
Of course it is best to do this with earphones or headphones because otherwise you will suffer from feedback.
I also use an external microphone (a Sennheiser MKE400) and separate headphones (a Sennheiser Momentum 4).
To get all this working I started with an
usb splitter that has usb-c on one end and two 3.5mm jacks on the other.
It did take me a while to find the right splitter.

This works but I had been experiencing static noise for some time.
So I decided to change the configuration.
I bought from Sennheiser a 3.5 mm jack cable with a usb-c jack at the other end.
The headphones also have a usb-c output anyway.

Then I started with a usb-c male to 2 usb-c female output splitter.
But I never really got this to work properly.

My current solution is to connect the two devices to the smartphone via a usb-c hub.

I first tried this at home and this seemed to work.
My test consisted of tapping the microphone itself a few times and that sound did come through on the headphones.

But when I use this setup at a real competition the sound is really bad.
If I connect just the microphone (directly or through the hub) and then the headphones through a Bluetooth connection then it works fine.
But this solution has the big disadvantage that the sound always comes through with a delay.

I also tried the same setup on a Samsung S23 Ultra with the same result.
So I don't think there is anything wrong with the smartphone.

But now, of course, I am left with the question of what exactly is wrong and how I could fix it.
Is this a hardware limitation of a Samsung ultra or is the problem with Filmic?

But I'm afraid not many people use the same set-up.

So anyway I ask on this forum if anyone has already tried something similar

[Obsydian]

My advice mate, keep it simple, anything with audio/video and too many links is ok when it works but a nightmare to figure out when it doesn't

Why the splitter can you not multipoint connect as BT devices ?

I use a simpler Sennheiser which coupled with the app syncs the audio to video, never even occurred to me before syncing could be an issue.

https://www.sennheiser.com/en-gb/catalog/archive/memory-mic/memory-mic-508214

[Piet9]

Ok you say Bluetooth.
I guess a the mic will have the same issue as the headphones.
The configuration that works right now is a mic connected by cable to the phone and the headphones through BT.
But the problem then is that the sound comes in with a delay and I wanted to avoid this by using cable connections.
If I start using a mic through BT I think this problem will only get worse.

[Piet9]

I looked a litthe further adn then I found this
https://www.kvraudio.com/forum/viewtopic.php?t=584005 

The most important over there is

Hi. Is there an Android audio recorder app that lets you monitor the recorded sound in real time? I only found one named Morec, but it's unusable because of the delay. Maybe there is a better one? Thanks.

The Android OS kernel is badly designed for real-time audio. This is why you are getting latency, and there's not much any developer can do about it.

Monitoring means there's latency twice in the audio path: from physical input to the app, then again from the app to the physical output.

The best advice I can give you is to try the iOs world of iPads and iPhones.

Now my question is, is this still true?
Can someone verify this because I only found it there and so I don't know tof this is correct.
If this is correct then I am going to have lag with both wired and bluetooth connection.

[garymitsy]

Did you solve the issue?
I can't connect any usb c mic or headphones. Although I can charge and connect to laptop. Has made my very expensive wireless microphones un usable?