Not sure Matt, this is the spec it has below, not noticed when I have been through the settings on the Pioneer anything about Ipod, just remember seeing an Aux section on the unit.....
Specifications
Tuner Features DEH-P88RS-II
Radio Data System (RDS) Yes
Best Stations Memory (BSM) Yes
PTY Search Yes
CD Player Features DEH-P88RS-II
CD Text Yes
Disc Title Memory Yes
Audio DEH-P88RS-II
Built in DSP Yes
Main features DEH-P88RS-II
Max. Power Output MOSFET 50W x 4
Audio DEH-P88RS-II
D/A Converter 1-bit Burr-Brown D/A Converter
Graphic Equaliser 16-band, with 5 pre-set curves and 2 custom curves
Main features DEH-P88RS-II
Tuner AM/FM
Plays CD-R, CD-RW, MP3, WMA, WAV, AAC (iTunes)
Front Panel Auto-flap mechanism (motorised)
Display Illumination White
Button Illumination White
Rotary Commander Yes
Remote Control Included
Multi-Language Display Yes
Cellular telephone auto muting Yes
Connectivity DEH-P88RS-II
Aux-in Yes (Rear-In)
Hard-wired Remote Input Yes
High Voltage Output 5V
IP Bus Yes
RCA Preout 3 (F + R + S.W or NON-FAD)
Sub-display Output Yes
Audio DEH-P88RS-II
Auto EQ Yes
Auto Time Alignment Yes
ASL (Automatic Sound Leveliser) Yes
High Pass Filter Yes
Low Pass Filter Yes
Listening Position Selector Yes
Loudness Yes
Source Level Adjuster (SLA) Yes