TDA7492P Aux Without Bluetooth problem

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Hello!,
I've bought on AliExpress my TDA7492p amp with board and everthing (link here). There is a Aux Input but this wont work without a bluetooth source.

For example if i plug Aux without bluetooth devices connected i hear nothing. But if i pair a bluetooh device and play something then i plug aux playing other thing i can hear both. Even ehen i turn on the amp with AuxIn when the amp is looking for a BT device make a noise and when noise is played i can hear the Aux.

BT Device Paired, not playing = no Audio from AuxIn;
BT Device Paired , playing anything = Normal Audio on AuxIn;
no BT Device Paired = no AuxIn audio;

what can i do or what i'm doing wrong, my priority is Aux, i want use amp on pc over aux BT isn't my necessity.

i'm not sure if what i write is clear and i can record a video if you want.
 
something that i notice, when a BT device is connected if you press Vol +/- button you should hear a beep, but on my amp this only happen if BT is playing something if you wont playing nothing even with the BT device connected you cant hear nothing.

@hari655what is your font voltage? i`m using a 9V (the minimium required by specification) i'm thinking maybe is because of that
 
Now i understend, the Aux that come with the board is't a Aux-Out port, is a Aux-In port. You can test it by connectiong a BT Device, then connect a phone or something like that and play.
So i see there is a modification that we cando to ad a Aux-In i'm gonna try.
 
If your board is like the one I received from an Ebay seller today, then I think I have figured out what the problem is - it's not an aux in port. At least not a stereo aux input like I, and probably everyone else who has bought one, thought it would be. I'm certain it is a mono microphone input so that the amp can act as a Bluetooth hands-free phone adaptor, hence why it will only work when there is a Bluetooth connection. Frankly I have been misled and I'm not happy. The amp itself seems OK and even sounds quite good given the limited choice of speaker drivers I have to hand to test it with. But without an aux in it's not what I needed. Also the BT won't synch with my old Samsung tablet and the case that came with it is pretty useless because the buttons supplied don't fit, they are designed to fit a board with taller micro-switches. Typical cheap Chinese BS, I think I will pursue a refund.
 
Fixed it

Hi! I know that I am almost a year too late, but i have found a fix! (Just in case someone else runs into this issue).

Just connect pin 8 and 10 on the Bluetooth module, like shown in the pictures.
Then the amplifier will not turn off, even though no device is connected via Bluetooth. The reason being, that pin 8 is responsible for turning on the amplifier with 1.5V, when a device is connected, and pin 10 being 1.5V.

It took some trial and error, but when you know the solution it is an easy fix.

Hope it helps.

IMG_0163.jpg
CSR 8635 Modul.jpg
 
I’ve done BrixS’s mod and, sure enough, the amp is powered without a Bluetooth connection. On my board, the output level is fixed, though: It seems the volume controls don't work unless Bluetooth is connected. I know there are a number of variants of the TDA7492P amp. Is this just a “feature” of my board, or is this common?
 
I’ve done BrixS’s mod and, sure enough, the amp is powered without a Bluetooth connection. On my board, the output level is fixed, though: It seems the volume controls don't work unless Bluetooth is connected. I know there are a number of variants of the TDA7492P amp. Is this just a “feature” of my board, or is this common?


Same thing here! My bord is a HW-337. Did you manage to fix the issue?
 
Sounds nice with this easy fix!

Did you guys find out if it is mono or stereo input?

I have now made this fix myself and it works perfectly! Thanks so much.

I soldered a jumper between the two pins so I can easily revert to the original mode if needed.

And yes, the AUX input is stereo!

I don't find the input level low at all. I use it with a Chromecast Audio which together with the amp makes a nice streaming system. Better than Bluetooth since the phone doesn't need to be near the amp.

My Denon Ceol RCN N8 has blown up the power board so I use this as a replacement until I get it fixed. And honestly, without the Denon playing simultaneously I can't tell the difference!

One nice hack would be to make the volume buttons work without bluetooth. Hope someone eventually finds a fix for this :)
 
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