Do incoming messaged get recorded at normal volume?
First, confirm that the unit is in good mechanical condition. See the section: General guide to tape deck cleaning and rubber parts replacement. Clean the tape head and inspect for anything that may be interfering with good tape-head contact. Clean the internal record/play selector switches. Dirty contacts can result in any number of symptoms. Assuming that none of this helps significantly, you are left with a problem in the electronics. If local record and playback of the the outgoing message works normally, the problem is not a bad tape head. It is probably in the interface to the phone line. If local record and/or playback do not work correctly, then there are likely problems with that circuitry. One other slight possibility is that you have so much equipment (phones, modems, fax machines, etc.) on the phone line that in your house that the answering machine is not able to drive the line properly and reduced outgoing message volume is the result.
