Hi
If air traffic are hard to understand because of a poor signal you could turn off or adjust the intercom in the aircraft. I find this really helps and makes the radio more clear.
Some aircraft have an intercom switch (Some R22s) this can be turned on or off.
If you fly an aircraft that has a intercom volume knob or squelch knob both of these can be adjusted or turned off.
Get your instructor to show you how.