Hello ecclectique, big disappointment. The GZ-34 did not solve the problem. On the contrary, with it in place of the Mullard GZ-37 the funny sounds began just a couple of minutes after begin of vinyl play... The GZ-34 is a Valvo with Mullard codes, not a Hytron. The seller wrote it measures good on his Funke tube tester. Any idea what else it could be? Thanks.
Regards,
frankiealverti
Regards,
frankiealverti