Communication. If he thinks everything is alright then nothing will ever change. You need to tell him what you want without making him feel like he is lacking. Try saying things to him like, "I really like it when you..."

How long have you been together? 4 years, I wouldn't worry. 4 months, you may have a problem lol.

Sometimes we just get so in the "groove" of things that it gets boring! Probably all you need is some communication (maybe he's feeling the same way!) and a little something new to spice things up.

communication ,talking sexy ,planning an evening just for that purpose, dress sexy. Could be many things to give your love life a jump start.

definately be talking about it, and hell bring the toy into bed withyou and him, i'm sure he would love it, I know i do when my wife does

we have been together for just over 2 years,
and i tried that medic36. and he didnt enjoy it when i bought the toy to bed.

u know sorry but most men are selfish babe, most women cant cum unless they play with their clit while there partner shaggs them? sex toys are fine but dont forget to shag as thats the emotional bonding bit? ive been through so much shit and my dh is so great sex doesnt really bother either us now as just being there for each other is more important, sex is just the icing on the cake. find out what you like and then show him, most men find that a turn on and play your pleasure/my pleasure nights?

As all of the above have said it talking matey!! From a guys perspective if you tell him that sex is boring, he will do whatever he can to spice it up. But having said that most of us guys are oblivious to things unless its put right in our faces, so you may have to be more direct with him. Its a guy thing, hints just don't work!
I went through this with an ex, and its different with everyone but maybe try something a little different? eg role play, costumes, maybe even a third party. Anyway mate i hope it gets better for you. All the best
Lee