Music and background sound are often used in virtual realities for creating an emotional atmosphere. The present study investigates how music or an ambient soundscape influence presence, the feeling of “being there”, as well as positive and negative affect. Fifty-one subjects participated, taking a stroll through a virtual park presented via a head-mounted display while they were walking on a treadmill. Sound was varied within subjects in four audio conditions: In a randomized sequence, participants experienced silence, a nature soundscape and music of positive or negative valence. In addition, time of day (daytime vs. nighttime walk) in the virtual environment was varied between subjects. Afterwards they were asked to rate their experience of presence and the positive and negative affect experienced. Results indicated that replaying any kind of sound lead to higher presence ratings compared to no sound at all, but there was no difference between playing a soundscape or music. Background music, however, tended to induce the expected emotions, though somewhat dependent on the musical pieces chosen. Further studies might evaluate whether it is possible to induce emotions through positive or negative (non-musical) soundscapes as well.