Solo-ing a column channel doesn't fully mute others

[tblrchstr]

Environment

• OS: all
• Giada version: 1.1.0

To Reproduce
Steps to reproduce the behavior:

1. add two channels in two different columns;
2. add a delay or reverb to column channel 2;
3. play both channels;
4. solo column channel 1;
5. you can still hear the delay or reverb tail from column channel 2.

Expected behavior
Only channel 1 should be rendered, with no extra audio leftovers from other channels.