Thank you for the responses so far. I wanted to provide an update and further clarify my issue. I have both amplifiers connected with 3.5mm stereo cables, and they are working well together. However, there is still no sound coming from the front channels when using the MX121.
I live outside the United States and have been unable to create an account on McIntosh’s website to reach out for support. I’m not sure if they accept international calls, so I haven’t been able to contact them directly.
Any further suggestions on how to resolve this issue or how to best get in touch with McIntosh support from abroad would be greatly appreciated.
Thank you again for your help!