Doctors have been fairly evenly divided for years on whether or not to
syringe and I have been doing my own since about 1972.   Periodically
if there is a build-up of wax that Otex type drops (mild hydrogen
peroxide) or Olive Oil will not soften and remove then the only way to
get rid of the wax is syringing.   Some methods are much safer than
others.

Recently I went to my audiologist to have an acoustic feedback whistle
attended to in the right ear digital hearing aid.  He discovered the
problem was caused by a large plug of wax that I didn't know I had let
accumulate.  I didn't have the usual symptoms of clicking and varying
deafness.  The waxt had partly darkened indicating that it had
hardened and stuck to the wall of the ear-canal.   This was causing
the sound to bouncing back off the wax and prevent much of it from
reaching the drum.   So I went home and syringed my own ear and
removed the wax very gently.  This is something that I don't recommend
anyone trying unless they are fairly dextrous with their hands.   I
have to use water at blood temperature ( 98.4 f) otherwise it can
upset the semi-circular canal temperature and make you dizzy as hell
and is dangerous.  
You can also upset the canal temperature if you over force the water
in at too much pressure and this is why I think it's dangerous to
allow someone else to syringe your ears if they're going to use the
forced water technique.  How do they know where your pain tolerance is
and hence your damage barrier?  They don't and not all of those on the
business end of the syringe are sufficiently sensitive to do it.
Some people naturally thump a piano keyboard and others carress it
without having to be shown.   Some people just don't know when they're
being brutal.

Now our local GP has a newer technique not forcing water in at all,
and he and his nursing staff, use very slight suction in a narrow pipe
placed in the ear and the suction created by a little automatic device
that only ever sucks to a certain safe level. No pain and very
efficient in operation.  The ear-canal is not sealed off and there's
no danger of sucking your brains out through the device either !  It
does however, very gently remove the wax.  

The problem was solved by my own self administration but in answer to
the person who said your ears itch when made too clean - they
shouldn't do.  You can't over clean the ear canal, unless you go
cleaning to the point of causing inflammation.  
New secretions begin immediately you clean it anyway.  It's important
to put some drops in; either olive oil or proper ear drops to
lubricate it just after cleaning.  Place a ball of sterile cotton wool
in for a few hours and then expose the ear to the outside air
gradually by removing the cotton wool for a few hours at a time
especially if the outside air temperature is very cold.
No itching should occur unless you have an infection or have
a skin condition.

I don't know why I'm telling you all this, I'm not a doctor but my
brother is and I know that many doctors think that self treatment is
often a very good thing, if the patient is enlightened and bothers to
study the details of what they're doing and why, because nobody knows
you like you know yourself.  

I forgot to say that when the wax had built up there was a noticable
increase in tinnitus.  It fell back to the normal level when the wax
was removed.

Also the wax caused ear ache.  Sufficient to need to take a pain
killing tablet and then the moment the wax was removed there was no
repeat of the ear ache at all.

So the presence of debris particularly wax can indeed cause tinnitus
as a side effect.  I don't think it is a creator of permanent
tinnitus, it's just a response to the pressure on the drum caused by
the wax if that wax is sufficiently hard as a kind of plug. It then
consititues and behaves like a foreign body rather than just ear
secretions which are natural.