I don't have a board to examine, but based on the photo you've shown I can see that it's a Philips part, in that particular in-line package that suggests a need for good thermal dissipation (thus, power handling capacity). It's in the speaker path, so probably an audio amp, and then there's the remains of the marking, ending in either 856 or 056. Some quick digging suggests that it's probably a TDA7056 "3 W mono BTL audio output amplifier", which is specifically noted for being able to drive an 8-ohm speaker at 1 watt with a 6v supply and no heatsink.