The music is too loud.
Stress 'AL-ta'. 'Troppo' = TROP-po — the double 'p' is pronounced distinctly.
Say this politely to a staff member if the background music in the gym is uncomfortably loud and is affecting your concentration or causing discomfort.
'Alta' when referring to sound means 'loud' (literally 'high'). 'Troppo' = too much/too. 'La musica è troppo alta' is the most natural way. You can also say 'il volume è troppo alto' (the volume is too high).
Potete abbassare la musica?
Can you turn the music down?
Direct request.
Il volume è un po' alto.
The volume is a bit high.
Softer, diplomatic phrasing.
Non riesco a concentrarmi con questa musica.
I can't concentrate with this music.
Explaining the impact.
Italian gyms typically play a mix of Italian pop ('musica italiana'), international hits, and workout EDM. 'Radio DeeJay' and 'RTL 102.5' are the most common background stations. Some gyms allow members to vote on the playlist via a gym app.