Ibanez S270

I have a s270 mol too just like you and unfortunantely the same happened to me,the guitar wouldn't stay in tume,so what i did was change that tremolo system for another ibanez one,the lo-trs that is cheap and now its double locked.the guitar never lost tune again,the tremelo stabiliser will not work because the string its still inside the back tremolo screw loose,so its no point even if you dont use the tremolo but you bend a string it will still detune it.after changing the tremolo what i did to the pickups was throw them to the garbage!they are horrible,in the bridge i put a dimarzio air norton,in the neck a paf pro and in the middle a seymour duncan little 59' humbucker,before i couldn't use the middle pickup because it would start humming like crazy now its quiet like hell plus i took all the sponge protectors under the middle pickupabd just put a little thin one and screw it with 2 smaller screws (half inch or 1,5 cm) otherwise they will come out inside the back cavity next to the springs,now the pickup its very low but because its a humbucker as well like the others the intensity of sound its allmost the same plus the little 59 all the pickup poles its screws so you can put them even lower or higher,if it was a single pickup you would really notice a big diference in sound ...i hope this helps!

The ibanez lo-trs fits in the S but in some year models the screw holes that keep the bridge in place need to be adjusted,another option its a schaller standard f. rose made bridge,its not as "low" in profile like the trs but the lengh from the screws its the same so you dont have to adjust it to put the trs.and its so good that you can even pick up the gritar my the wammy bar and shake it like steve vai does it and it will never go out of tune.
I curentely have the S with a ernie ball pickup selector because the original ibanez one with time starts to have bad connections,in the bridge i put a air norton ,in the middle a little 59 (s.d.)and a paf pro in the neck,the sound its very similar to satriani because the air norton its between the sound of a paf pro and a Striani disigned "fred" but with more middle frequencies for soloing like joe petrucci sound.having it with a humbucker in the middle makes it to have a warm sound without any peaks like the les pauls that have 3 humbuckers makes it perfect plus when the pick selector its in position 2 or 3 out of 5 for example the bridge pick up its full on and half of the middle one its working so you allways have a full fat sound because you have 2 humbuckers working all the time ...its my personal guitar but i am the owner have a studio/rehearsal room and everyone that goes there asks me to play with it ...i think i found the right pickup and bridge combination that makes from this cheap ibanez one as good as any S prestige one...

dont forget that if you compare the wiring diagrams from dimarzio and S.D. for example their color code for the wires its diferent,sometimes what its red in dimarzio. its black in s.d. and the oposite too i think the s.d. ones its the other way around ,and differs from most pickup makes compare first for example a simple HsH comfiguration from both Dimarzio and Seymour Duncan from their websites and figure out with one you will have to change to make it work,i had to do the same otherwise you will get it wrong and doesent work or in best case it would work but in reverse pickup polarity (makes a cool mellow sound but it only works at like 50% or 75 % pickup output).it happened to me as well and i tried like a arse to figure it out intil if really looked at the squemathics from both websites and noticed they use diferent colourswhat i did ultimately was to take a black and white copy of the squemathic and with colour markers i made where my wires would go allready with the decoded colours otherwise i would mess it up again

That i dont know mate,i have a washburn nuno bettencourt model with the factory installed bill lawrence but never liked the sound,its too much hi and middle frequences and no bass at all but ive noticed some blinking sounds sometimes.maybe its from beeing upside down or too close to the strings,mine its as low as it gets and it still making weird sounds... but try to reverse polatity and see what happens plus ive seen in the s.d. website that there are some special ways to conect the 4 wires that make the pickup have less power but keepsit more silent,i prefer the dimarzio duosonic like john petrucci uses.
maybe its the wiring ,or try to isolate all the body cavities with cooper sheet to isolate not just where the potenciometers are but the cavities where the pickups are too and conect the cooperplate from the potenciometer cavitie to the earth wire too i did this in mine for extra silent to prevent humms and cracks when i change pickups with the selectoror sometimes its the jack where you conect the guitar.to prevent this because gets a bit too loose after long use on olg guitars i only use planet waves cable that have a kind of lumps from the side on the jack to fill the hole totaly .wiring its allways a pain in the butt because sometimes you just have to use low quality wielding material with the hot iron for it to go weird and sound weird too...in one of my other ibanez guitars everything stopped blinking when i used the planet waves cable...

you can see it here ,the one i use:

store.daddario.com/category/394640/Custom_Series_with_Compression_Springs

notice the "springs" around the jack