Introducing the S8 Mini Stereo RCA 4-Channel Passive Mini Mixer
It takes the Amiga's audio output and mixes both left and right channels to merge the audio.  So instead of the normal 2 amiga audio-channels of sound from the left and 2 channels from the right, you'll get 4 channels on the left and 4 on the right. 
 
With the S8 Mini Stereo Mixer there's no more drums coming out the left speaker and chorus out the right, You'll get drums and chorus on both the left and the right speakers.
 
More Info about our Mini Audio Mixer:
A compact passive mixer is a stereo four-way passive mixer for extended control tuning, mixing instrument, audio players, tape player, computer, mobile phone, tablet and so on.
 
No battery or other power source required.
 
The device can also be used as a 1 in / 4 out stereo distributor (clockwise to adjust the volume).

OUTPUT: is used to connect RCA jack or 3.5mm socket to your speakers.
INPUT 1-4: controls the signal level from input 1-4 (Amiga used 2 of the Inputs)
 
Four independently regulated 100K ohmic potentiometers.
Colour: Black
Construction: Metal
Input impedance: 10K ohms to 47K ohms
Output impedance: 2.5K ohms to 10K ohms
Gain: -12dB MAX
Net weight: 0.2 kg
Product size: 83 x 52 x 38 mm
 
Includes the three Amiga audio cables you'll likely need to connect to your stereo speakers.