I noticed that too and found that I had to increase the levels of the paths on the Helix and also, sometimes, the levels of the amps too. You might want to look at the block volume levels too. I found that when I turn the paths up to around 2 to 5 and the main volume knob of the Helix to around 11 and the Powercab to around 11 as well, it's gets pretty loud without clipping. Also, on the Powercab, you might need to turn of the level for each speaker model. Some speakers are quieter or louder than others, that I have noticed,