MISSING DTMF TONES BOTH IN RECEIVING AND TRANSMITTING

missing dtmf

Dear Friends

Currently I am working on a Intruder Alarm system project with auto-dialer facility.
In our system we dial the remote user during security break-up, also we are giving facility to control the system using DTMF keys from the remote side.
Now we are facing some problems:

(1) Initially we designed the hardware, then we wrote the software and the system was running fine on our intercom lines(EPABX CONTROLLED OFFICE INTERCOM LINES). here we are using two digit -dialling ( e.g. 30,31,24 etc)
(2) Then we started testing the system on PSTN LINES, then problems started .
We are using HT9200A FOR DTMF TRANSMITTING and HT9170 FOR DTMF RECEIVING. On PSTN LINES we are unable to receive DTMF TONES, It is giving some delay and sometime it couldnt receive some DTMF tones. We observe that we have to keep pressing the TELEPHONE HANDSET keys for some time(around 2 sec), then only the system receives the codes and sometime it misses some DTMF KEYS. But it is running fine on EPABX intercom lines.
(3) Similarly when the sytem dials any PSTN OR MOBILE PHONE phone no, we observe that it misses some digits of the phone no in some random fashion. We have checked it through TELEPHONE NO ANALYZER. Sometime it misses two digits, sometime one , sometime three also randomly. It tells that the sytem doesnt send all the digits during dialling. But the same dialling event is running fine on EPABX INTERCOM LINES.

We tried to change the values of some components in our hardware board, but it is not running well.

i m sending two schmatics:

(1) dialer_sch1.pdf ( Micro-controller section )
(2) dialer_sch2.pdf ( Dialer section )

So please check our CIRCUIT and give us some solutions.

Regards

Rajib

plz chks these points.
1- change crystals of both sed/rcv.
2- note wave form of pstn line during send /recv.

i hope u will find solution.